Systems and methods for prosthetic wrist rotation

ABSTRACT

Features for a prosthetic wrist and associated methods are described. The wrist couples with a prosthetic socket and a prosthetic hand. The wrist may rotate the hand. The wrist includes features to prevent or mitigate undesirable separation of the wrist from the socket. The wrist may have an expanding coupling, such as an expanding ring, to better secure the wrist with the socket. An actuator may cause the coupling to expand outward to prevent or mitigate undesirable separation of the wrist from the socket. Alternatively or in addition, the wrist may include torque control features to prevent undesirable or premature separation of the hand from the wrist, for example when using a “quick wrist disconnect” (QWD) apparatus. A torque control method may tailor or limit multiple torques to be applied by the wrist to the hand based on operational requirements and phases, such as anticipated torque loads and operational timing.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are hereby incorporated by reference under 37 CFR 1.57.

This application is a continuation of U.S. patent application Ser. No.16/204,059, filed Nov. 29, 2018, entitled SYSTEMS AND METHODS FORPROSTHETIC WRIST ROTATION, which is a continuation-in-part of U.S.patent application Ser. No. 15/341,939, filed Nov. 2, 2016, entitledSYSTEMS AND METHODS FOR PROSTHETIC WRIST ROTATION, now U.S. Pat. No.10,369,024 issued on Aug. 6, 2019, which claims the benefit of U.S.Provisional Patent Application No. 62/382,919, filed Sep. 2, 2016,entitled SYSTEMS AND METHODS FOR PROSTHETIC WRIST ROTATION, thedisclosure of each of which is incorporated herein by reference in itsentirety for all purposes.

BACKGROUND Field

Described herein are features related to prosthetics, for example aprosthetic hand and wrist system and associated methods.

Description of the Related Art

Hand and arm amputees benefit greatly from prosthetic replacements.Prosthetic hands, wrists, and/or arms restore lost functionality andprovide independence to users. However, existing solutions havedeficient wrist control. For instance, existing solutions causeresponsive delay with wrist rotation that detracts from more closelymimicking the functionality of a natural wrist. As another example,existing solutions insufficiently synchronize wrist movement with otherprosthetic movements, such as grip formation with a prosthetic handand/or rotation of a prosthetic arm, which detracts from more closelymimicking the functionality of a natural limb. Further, existingsolutions have deficient connection and disconnection features forattaching and removing the prosthetics from a user. Improved prostheticwrist solutions without these and other drawbacks are thereforedesirable.

SUMMARY

The embodiments disclosed herein each have several aspects no single oneof which is solely responsible for the disclosure's desirableattributes. Without limiting the scope of this disclosure, its moreprominent features will now be briefly discussed. After considering thisdiscussion, and particularly after reading the section entitled“Detailed Description,” one will understand how the features of theembodiments described herein provide advantages over existing systems,devices and methods.

The following disclosure describes non-limiting examples of someembodiments. For instance, other embodiments of the disclosed systemsand methods may or may not include the features described herein.Moreover, disclosed advantages and benefits can apply only to certainembodiments of the invention and should not be used to limit thedisclosure.

Features for a prosthetic wrist and associated methods are described.The wrist couples with a prosthetic socket and a prosthetic hand. Thewrist may rotate the hand. The wrist includes features to prevent ormitigate undesirable separation of the wrist from the socket. The wristmay have an expanding coupling, such as an expanding ring, to bettersecure the wrist with the socket. An actuator may cause the coupling toexpand outward to prevent or mitigate undesirable separation of thewrist from the socket. Alternatively or in addition, the wrist mayinclude torque control features to prevent undesirable or prematureseparation of the hand from the wrist, for example when using a “quickwrist disconnect” (QWD) apparatus. The QWD apparatus may allow forconnection and/or removal of a prosthetic hand by rotation of the hand,for example application of a torque. A torque control method may tailoror limit the torque applied by the wrist to the hand based onoperational requirements and phases, such as anticipated torque loadsand operational timing, to prevent undesirable results such as prematurerelease of the hand.

In one aspect, a prosthetic wrist is described comprising a body, afirst actuator and a coupling. The body extends along an axis from aproximal end to a distal end, with the proximal end configured to couplewith a prosthetic socket of a user and the distal end configured tocouple with a prosthetic hand. The first actuator is coupled with thebody and configured to rotate the prosthetic hand when the prostheticwrist is coupled with the prosthetic hand. The coupling extendscircumferentially about the body providing an expansive circumferentialbarrier to the body and configured to expand.

Various embodiments of the various aspects may be implemented. Thecoupling may be attached to an outer portion of the body. The couplingmay comprise an expanding ring. The expanding ring may extend at leastpartially around the body and be configured to have an increased widthin an expanded configuration as compared to an unexpanded configuration.The expanding ring may extend at least partially around the body and beconfigured to have an increased circumference in an expandedconfiguration as compared to an unexpanded configuration. The expandingring may be configured to move axially from an expanded configuration toan unexpanded configuration. The expanding ring may be configured tomove proximally from the expanded configuration to the unexpandedconfiguration. The prosthetic wrist may further comprise a secondactuator configured to move the coupling from an expanded configurationto an unexpanded configuration. The second actuator may comprise arotatable shaft. The prosthetic wrist may further comprise a pressurering extending at least partially around the body, with the secondactuator configured to cause movement of the pressure ring, wheremovement of the pressure ring causes the expanding ring to expand. Thesecond actuator may be configured to bear against the pressure ring tocause the movement of the pressure ring, with the pressure ringconfigured to bear against the expanding ring to move the expanding ringaxially, and the expanding ring in response to moving axially configuredto expand due to engagement with an angled projection of the body.

In another aspect, a prosthetic wrist is described comprising a body, afirst actuator and an expanding ring. The body extends along an axisfrom a proximal end to a distal end, with the proximal end configured tocouple with a prosthetic socket of a user and the distal end configuredto couple with a prosthetic hand. The first actuator is coupled with thebody and is configured to rotate the prosthetic hand when the prostheticwrist is coupled with the prosthetic hand. The expanding ring at leastpartially surrounds the body and is configured to at least partiallyexpand from a first location to a second location that is farther fromthe axis than the first location.

Various embodiments of the various aspects may be implemented. Theexpanding ring may be configured to at least partially expand in aradial direction. The prosthetic wrist may further comprise a secondactuator configured to cause the expanding ring to expand to the secondlocation. The second actuator may be configured to move the expandingring axially, where axial movement of the expanding ring causes theexpanding ring to expand to the second location. The prosthetic wristmay further comprise a pressure ring, where the second actuator isconfigured to move the pressure ring axially to thereby cause axialmovement of the expanding ring, and where axial movement of theexpanding ring causes the expanding ring to expand to the secondlocation. The second actuator may comprise a rotatable shaft.

In another aspect, a method of securing a prosthetic wrist with aprosthetic socket is described. The method comprises attaching a body ofthe prosthetic wrist with a prosthetic socket of a user, the bodydefining an axis, rotating a rotatable shaft that is coupled with thebody to cause the shaft to move axially, and expanding the couplingoutward away from the body in response to axial movement of thecoupling, to better secure the prosthetic wrist with the prostheticsocket of the user when the prosthetic wrist is coupled with theprosthetic socket. The method may further comprise moving a pressurering axially in response to axial movement of the rotatable shaft, whereaxial movement of the pressure ring causes the expanding ring to moveaxially and thereby expand

Further, features for enhancing the wrist/socket connection and fortorque control may be used with hand and wrist systems and methodsdescribed herein to provide a more responsive upper limb prostheticsystem for amputees. In some embodiments, the rotation of a prostheticwrist is performed in conjunction with the formation of a grip with acorresponding prosthetic hand. Users can command a particular grip to beformed with the prosthetic hand, and the prosthetic wrist will rotateresponsively and in an efficient manner to simulate natural hand andwrist movement.

In another aspect, a prosthetic hand and wrist system is described. Theprosthetic hand and wrist system comprises a prosthetic hand, aprosthetic wrist, and an inertial measurement unit (IMU) attached to theprosthetic hand. The prosthetic wrist comprises a fixed portion, anactuator, and a rotatable portion. The fixed portion is configured toattach to an arm, the rotatable portion is configured to attach to theprosthetic hand, and the actuator is attached to both the fixed androtatable portions and is configured to actuate the rotatable portionrelative to the fixed portion thereby rotating the prosthetic hand. TheIMU is configured to detect an orientation of the prosthetic hand. Aprocessor in communication with the IMU and the actuator is configuredto execute a set of instructions to perform a method to control theactuator. The set of instructions may be stored in a memory located onthe prosthetic hand, the prosthetic wrist or remotely. The methodexecuted by the set of instructions comprises receiving data from theIMU associated with the orientation of the prosthetic hand, identifyinga desired grip for the prosthetic hand, determining a rotation for theprosthetic hand based on i) the data from the IMU and ii) the desiredgrip, and causing the actuator to perform the rotation for theprosthetic hand by actuating the rotatable portion.

In some embodiments, identifying the desired grip for the prosthetichand comprises receiving an electromyography (EMG) signal from a user ofthe prosthetic hand and wrist system, detecting a gesture movementperformed by the user, and determining the desired grip based on thedetected gesture movement. In some embodiments, identifying the desiredgrip for the prosthetic hand further comprises prompting the user toperform the gesture movement. In some embodiments, prompting the user toperform the gesture movement comprises moving a finger of the prosthetichand.

In some embodiments, determining the rotation for the prosthetic handcomprises determining Euler angles for the prosthetic hand based on thedata from the IMU, and determining angular rotation data based on thedetermined Euler angles and on the desired grip. The angular rotationdata may comprise a direction and an angle of rotation. The angularrotation data may comprise a speed of rotation.

In some embodiments, the prosthetic hand and wrist system furthercomprises an actuator coupled with the prosthetic hand and configured toactuate to form the desired grip with the prosthetic hand. In someembodiments, the actuation of the prosthetic hand to the desired gripand the rotation of the prosthetic hand are performed simultaneously. Insome embodiments, the prosthetic hand and wrist system comprises aplurality of digit actuators coupled with a plurality of digits of theprosthetic hand, and the plurality of digit actuators are configured toactuate to form the desired grip with the prosthetic hand. In someembodiments, the prosthetic hand and wrist system further comprises adistal actuator coupled with a distal portion of the hand, and thedistal actuator is configured to rotate the hand about a pitch axis toform the desired grip with the prosthetic hand.

In some embodiments, the actuator is configured to cause rotation of theprosthetic hand about a single axis, such as a roll axis. The actuatormay be configured to cause rotation of the prosthetic hand about two ormore axes. The actuator may be configured to cause rotation of theprosthetic hand about a pitch axis and a roll axis.

In some embodiments, the IMU comprises a nine-axis IMU including threeaccelerometers, three gyroscopes and three magnetometers.

In some embodiments, the arm is a natural arm. In some embodiments, thearm is a prosthetic arm. The prosthetic arm may be actuatable andinclude an elbow joint and/or a shoulder joint. The actuatableprosthetic arm may be controlled in conjunction with rotation of theprosthetic wrist and formation of a grip with the prosthetic hand. Anelbow joint and/or a shoulder joint may be controllably actuated, forexample rotated. In some embodiments, a prosthetic system includes therotatable prosthetic wrist, the prosthetic hand configured to form agrip, a prosthetic arm having an actuatable elbow joint and/or shoulderjoint. Additional IMUS may be included in the additional prostheticcomponents, for example with the actuatable arm to detect and measureorientations of one or more segments of the prosthetic arm, such asrotation about the elbow and/or shoulder. Rotation of the prostheticwrist and formation of the grip with the prosthetic hand may beperformed in conjunction with rotation of the elbow and./or shoulderjoints of the prosthetic arm and based on IMU data and selection of agrip.

In another aspect, a prosthetic wrist is described. The prosthetic wristcomprises a fixed portion, a rotatable portion, an actuator module and aprocessor. The fixed portion is configured to attach to a prosthetic ornatural arm. The rotatable portion is configured to attach to aprosthetic hand that has an inertial measurement unit (IMU) to detect anorientation of the prosthetic hand. The actuator module is attached toboth the fixed and rotatable portions and configured to actuate therotatable portion relative to the fixed portion thereby rotating theprosthetic hand. The processor is in communication with the IMU and theactuator module and configured to execute a set of instructions toperform a method to control the actuator module. The method comprisesreceiving data from the IMU associated with the orientation of theprosthetic hand, identifying a desired grip for the prosthetic hand,determining a rotation for the rotatable portion based on i) the datafrom the IMU and ii) the desired grip, and causing the actuator moduleto perform the rotation.

In some embodiments of the prosthetic wrist, identifying the desiredgrip for the prosthetic hand comprises receiving an electromyography(EMG) signal from a user of the prosthetic wrist, detecting a gesturemovement performed by the user, and determining the desired grip basedon the detected gesture movement. Identifying the desired grip for theprosthetic hand may further comprise prompting the user to perform thegesture movement. Prompting the user to perform the gesture movement maycomprise moving a finger of the prosthetic hand.

In some embodiments of the prosthetic wrist, determining the rotationfor the prosthetic hand comprises determining Euler angles for theprosthetic hand based on the data from the IMU, and determining angularrotation data based on the determined Euler angles and on the desiredgrip. The angular rotation data may comprise a direction and an angle ofrotation. The angular rotation data may comprise a speed of rotation.

In another aspect, a method of rotating a prosthetic wrist is described.The method comprises receiving data from an inertial measurement unit(IMU) that is coupled with a prosthetic hand, wherein the data isassociated with an orientation of the prosthetic hand and the prosthetichand is attached to the prosthetic wrist; identifying a desired grip forthe prosthetic hand; determining a rotation for the prosthetic wristbased on i) the data from the IMU and ii) the desired grip, and causingthe prosthetic wrist to perform the rotation.

In some embodiments of the method, identifying the desired grip for theprosthetic hand comprises receiving an electromyography (EMG) signalfrom a user of the prosthetic wrist, detecting a gesture movementperformed by the user, and determining the desired grip based on thedetected gesture movement. Identifying the desired grip for theprosthetic hand may further comprise prompting the user to perform thegesture movement. Prompting the user to perform the gesture movement maycomprise moving a finger of the prosthetic hand.

In some embodiments of the method, determining the rotation for theprosthetic hand comprises determining Euler angles for the prosthetichand based on the data from the IMU, and determining angular rotationdata based on the determined Euler angles and on the desired grip. Theangular rotation data may comprise a direction and an angle of rotation.The angular rotation data may comprise a speed of rotation.

In some embodiments, the method may further comprise forming the desiredgrip with the prosthetic hand. Causing the prosthetic wrist to performthe rotation and forming the desired grip with the prosthetic hand maybe performed simultaneously.

In some embodiments of the method, the wrist rotation is about a singleaxis. The wrist rotation may be about two or more axes. The wristrotation may be about a pitch axis and a roll axis.

In some embodiments of the method, the IMU comprises a nine-axis IMUincluding three accelerometers, three gyroscopes and threemagnetometers.

In another aspect, another prosthetic hand and wrist system isdescribed. The system comprises a prosthetic hand and a prostheticwrist.

The prosthetic hand comprises a wrist attachment, a palm assembly, fourprosthetic finger digits and a prosthetic thumb digit. The wristattachment includes a connection ring and a ball bearing retainer on aproximal end of the wrist attachment. The palm assembly is attached tothe wrist attachment and includes a hand chassis, a dorsal fairing, apalm fairing, an inertial measurement unit (IMU), a printed circuitboard (PCB), and an on-off switch. The hand chassis is attached to thewrist attachment and includes structural walls having a motor assemblyand a thumb rotator attached thereto. The dorsal fairing is attached tothe hand chassis and faces in a dorsal direction forming a back of theprosthetic hand. The palm fairing is attached to the hand chassis and tothe dorsal fairing and forms a palm of the prosthetic hand, with thepalm and dorsal fairings forming a cavity therebetween. The IMU isattached to a dorsal side of the hand chassis and is configured todetect an orientation of the prosthetic hand. The PCB includes aprocessor and is attached to the hand chassis in the cavity formed bythe dorsal and palm fairings. The PCB is in electrical communicationwith the IMU, a battery and with motors that control the prostheticdigits. The on-off switch is attached to the hand chassis and is inelectrical communication with the PCB. A portion of the on-off switchmay protrude through an opening of the palm fairing.

The four prosthetic finger digits are rotatably attached in a spacedconfiguration along a distal end of the prosthetic hand. Each prostheticfinger digit includes a finger knuckle assembly, a worm wheel, agearbox, a knuckle fairing, a knuckle cap thinner, a retaining tabthinner, a wire, an extension spring and a fingertip assembly. Thefinger knuckle assembly is attached to the palm assembly. The worm wheelis attached at a proximal end to the finger knuckle assembly and has aportion with a hole. The gearbox contains a motor, a motor bearing, aworm gear, and a worm bearing therein, and includes two prongs havingaligned holes and extending toward the palm assembly and defining aspace in between the two prongs. The portion of the worm wheel with thehole is inserted into the space, and the gearbox is rotatably attachedto the worm wheel via a gearbox pivot pin extending through the alignedholes of the worm wheel and gearbox. The knuckle fairing is rotatablycoupled with the gearbox pivot pin and covers a distal portion of thegearbox. The knuckle cap thinner is connected to a distal end of thegearbox. The retaining tab thinner is rotatably connected to a distalend of the knuckle cap thinner. The wire connects the finger knuckleassembly to the retaining tab thinner and extends over a hinge pointsuch that a closing rotation of the gearbox will pull on the wire androtate the retaining tab thinner relative to the gearbox. The extensionspring connects the retaining tab thinner to the gearbox such that theclosing rotation of the gearbox will extend the spring thus causing thespring to bias the retaining tab thinner to an opening rotation. Anopening rotation of the gearbox will cause the spring to pull on theretaining tab thinner to rotate the retaining tab thinner in an openingdirection. The fingertip assembly includes a finger extension and afingertip. The finger extension is attached to a distal end of theretaining tab thinner and the fingertip is attached to a distal end ofthe finger extension.

The prosthetic thumb digit is rotatably attached to a side of theprosthetic hand. The prosthetic thumb digit includes a thumb knuckleassembly, a worm wheel, a gearbox, a thumb fairing, a fixed fairing, anda thumb tip. The thumb knuckle assembly is attached to a side of thepalm assembly. The worm wheel is attached at a proximal end to thefinger knuckle assembly and has a portion with a hole. The gearboxcontains a motor, a motor bearing, a worm gear, and a worm bearingtherein. The gear box includes two prongs having aligned holes andextending toward the palm assembly and defining a space in between thetwo prongs. The portion of the worm wheel with the hole is inserted intothe space. The gearbox is rotatably attached to the worm wheel via agearbox pivot pin extending through the aligned holes of the worm wheeland gearbox. The thumb fairing is rotatably coupled with the gearboxpivot pin and covers a distal portion of the gearbox. The fixed fairingis coupled with the thumb knuckle assembly and covers a portion of thethumb fairing and covers a distal portion of the gearbox. The thumb tipis connected to a distal end of the gearbox.

The prosthetic wrist is attached to the prosthetic hand. The prostheticwrist comprises a circular bearing race, a circular threaded front, awrist actuator module, a pressure ring, a coupling piece, a coaxsubassembly, and a digital signal processor (DSP) cover.

The circular bearing race is located on a distal end of the prostheticwrist and is configured to receive therein a corresponding bearingcomponent for rotatable connection to the wrist attachment of theprosthetic hand. The circular threaded front is attached along an outercircumference of the bearing race and extends in the proximaldirectional.

The wrist actuator module comprises a body, an asynchronous motor (ASM),a motor driver printed circuit board (PCB), and the digital signalprocessor (DSP). The body defines a central passageway therethrough andhas a distal circumferential end attached along an outer circumferenceof a proximal portion of the threaded front. The asynchronous motor(ASM) is coupled with the body. The motor driver PCB is in electricalcommunication with the ASM and with the DSP.

The pressure ring is attached to the outside of the distal end of thewrist actuator module and secures the wrist actuator module to thethreaded front. The coupling piece has a base defining an openingtherethrough and a series of tabs projecting distally from an outer edgeof the base. The base is in mechanically communication with the wristactuator module and in mechanical communication with the ASM such thatrotation of the ASM will rotate the coupling piece. The coax subassemblyhas a cable extending through the central passageway of the wristactuator module and a plug extending distally through the opening of thecoupling piece. The digital signal processor (DSP) cover is attached toa proximal end of the wrist actuator module.

The DSP is disposed inside the DSP cover, with the DSP in electricalcommunication with the ASM and with the IMU of the prosthetic hand. TheDSP is in communication with a memory having a set of instructionswherein the DSP is configured to execute the set of instructions toperform a method to control the ASM to transmit rotation to theprosthetic hand. The method comprises receiving data from the IMUassociated with an orientation of the prosthetic hand, identifying adesired grip for the prosthetic hand, determining a rotation for theprosthetic hand based on i) the data from the IMU and ii) the desiredgrip, and causing the wrist actuator module to perform the rotation forthe prosthetic hand by driving the ASM.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present disclosure will becomemore fully apparent from the following description and appended claims,taken in conjunction with the accompanying drawings. Understanding thatthese drawings depict only several embodiments in accordance with thedisclosure and are not to be considered limiting of its scope, thedisclosure will be described with additional specificity and detailthrough use of the accompanying drawings. In the following detaileddescription, reference is made to the accompanying drawings, which forma part hereof. In the drawings, similar symbols typically identifysimilar components, unless context dictates otherwise. The illustrativeembodiments described in the detailed description, drawings, and claimsare not meant to be limiting. Other embodiments may be utilized, andother changes may be made, without departing from the spirit or scope ofthe subject matter presented here. It will be readily understood thatthe aspects of the present disclosure, as generally described herein,and illustrated in the drawing, can be arranged, substituted, combined,and designed in a wide variety of different configurations, all of whichare explicitly contemplated and make part of this disclosure.

FIG. 1 is a perspective view of an embodiment of a prosthetic hand andwrist system that includes a prosthetic hand and a prosthetic wrist.

FIG. 2A is a perspective view of the prosthetic wrist of FIG. 1.

FIG. 2B is a top view of the prosthetic wrist of FIG. 1.

FIG. 2C is an exploded view of the prosthetic wrist of FIG. 1.

FIG. 2D is a cross-section view of the prosthetic wrist of FIG. 1 takenalong the line 2D-2D indicated in FIG. 2B.

FIG. 2E is a cross-section view of the prosthetic wrist of FIG. 1 takenalong the line 2E-2E indicated in FIG. 2B.

FIG. 3A is a perspective view of the prosthetic hand of FIG. 1.

FIGS. 3B-3G are various views of the prosthetic hand of FIG. 1 with somecomponents removed for clarity.

FIGS. 3H and 31 are bottom perspective and bottom views, respectively,of the prosthetic hand of FIG. 1.

FIG. 4A is a perspective view of a prosthetic finger digit of theprosthetic hand of FIG. 1.

FIG. 4B is a side view of the prosthetic finger digit of FIG. 4A withsome components removed for clarity.

FIG. 4C is a side cross-section view of the prosthetic finger digit ofFIG. 4A having a wire and spring for rotating outer portions of theprosthetic finger.

FIG. 5A is a perspective view of a prosthetic thumb digit of theprosthetic hand of FIG. 1.

FIG. 5B is a side view of the prosthetic finger digit of FIG. 5A withsome components removed for clarity.

FIG. 6A is a perspective view of the prosthetic wrist of FIG. 1 attachedto an embodiment of a prosthetic lower arm.

FIG. 6B is a perspective view of the prosthetic wrist and arm of FIG. 6Awith the prosthetic hand of FIG. 1 shown detached from the prostheticwrist.

FIG. 6C is a perspective view of the prosthetic wrist and lower armsystem of FIG. 6A with the arm shown transparent for clarity, showing anelectromyography (EMG) system.

FIG. 7 is a perspective view of an embodiment of a prosthetic arm systemincorporating the prosthetic hand and wrist system of FIG. 1.

FIG. 8 is a perspective view of an embodiment of a prosthetic shoulderand arm system incorporating the prosthetic hand and wrist system ofFIG. 1.

FIG. 9A is a flowchart showing an embodiment of a method for using theprosthetic hand and wrist system of FIG. 1.

FIGS. 9B-9G are flowcharts showing embodiments of methods that may beused in combination with the method of FIG. 9A.

FIGS. 10A-10D are embodiments of remote devices that may be used withthe prosthetic hand and wrist system of FIG. 1.

FIG. 11 is an embodiment of a control system that may be used to controlthe prosthetic hand and wrist system of FIG. 1.

FIGS. 12A-12F are sequential perspective views of the prosthetic wristand arm of FIG. 6A showing simultaneous grip formation and rotation ofthe prosthetic hand.

FIG. 13A is a partial cross-section view of the prosthetic wrist of FIG.1 showing the expanding ring in an unexpanded configuration.

FIGS. 13B-13C are partial cross-section views of the prosthetic arm andwrist of FIG. 6A showing the prosthetic wrist with the expanding ring inan unexpanded configuration.

FIG. 14A is a partial cross-section view of the prosthetic wrist of FIG.1 showing the expanding ring in an expanded configuration.

FIGS. 14B-14C are partial cross-section views of the prosthetic arm andwrist of FIG. 6A showing the prosthetic wrist with the expanding ring inan expanded configuration.

FIGS. 15A-15C are data plots showing embodiments of relationshipsbetween current and time during rotation of a prosthetic wrist that maybe used for controlling torque of the prosthetic wrist of FIG. 1.

FIG. 16A is a flow chart showing an embodiment of a method for applyingtorque limits for control of the prosthetic wrist of FIG. 1.

FIG. 16B is a flow chart showing an embodiment of a method fordetermining torque limits for control of the prosthetic wrist of FIG. 1.

DETAILED DESCRIPTION

The following detailed description is directed to certain specificembodiments of the development. In this description, reference is madeto the drawings wherein like parts or steps may be designated with likenumerals throughout for clarity. Reference in this specification to “oneembodiment,” “an embodiment,” or “in some embodiments” means that aparticular feature, structure, or characteristic described in connectionwith the embodiment is included in at least one embodiment of theinvention. The appearances of the phrases “one embodiment,” “anembodiment,” or “in some embodiments” in various places in thespecification are not necessarily all referring to the same embodiment,nor are separate or alternative embodiments necessarily mutuallyexclusive of other embodiments. Moreover, various features are describedwhich may be exhibited by some embodiments and not by others. Similarly,various requirements are described which may be requirements for someembodiments but may not be requirements for other embodiments.

The prosthetic hand and wrist system and methods described hereinprovide a more responsive upper limb prosthetic system for amputees. Insome embodiments, the rotation of a prosthetic wrist is performed inconjunction with the formation of a grip with a corresponding prosthetichand. Users can command a particular grip to be formed with theprosthetic hand, and the prosthetic wrist will rotate responsively andin an efficient manner to simulate natural hand and wrist movement. Theprosthetic hand and wrist system and methods provide enhancedresponsiveness of wrist rotation and other advantages. A prosthetic handorientation sensor, such as an inertial measurement unit (IMU),communicates hand orientation data directly to one or more processors ofthe prosthetic wrist to determine wrist rotational position and thusnecessary rotational movements for a particular chosen grip. Thisbypasses the need for more complex and time-consuming solutions, such aswrist encoder analysis and/or electromyography (EMG) sensor commands forwrist rotation, which are more cumbersome and delayed when switchingfrom control of the prosthetic hand to the prosthetic wrist. By usingthe orientation sensor of the prosthetic hand to determine prostheticwrist rotation, the prosthetic hand and wrist movements are collectivelyassociated with orientation sensor data from only the prosthetic hand.The wrist rotation is thus more responsive to user commands, and moresynchronized with grip formation of the prosthetic hand. The orientationsensor may be a nine-axis IMU, for example having a three-axisgyroscope, a three-axis accelerometer and a three-axis magnetometer. Thedesired prosthetic hand grip can be indicated with translations of theprosthetic hand along pre-determined paths, with muscle movementsdetected by EMG sensors, with selections made with mobile devices suchas phones or wearables and/or with communicative sensors such as “gripchips” placed near or on items which the prosthetic hand may grasp. Inconjunction with indication of the desired grip, data from theorientation sensor associated with the current prosthetic handorientation is communicated to the prosthetic wrist. The necessary wristrotation is then determined and performed based on the currentorientation of the prosthetic hand and the indicated grip.

FIG. 1 is a perspective view of an embodiment of a prosthetic hand andwrist system 10. The prosthetic system 10 includes an embodiment of aprosthetic wrist 100 attached to an embodiment of a prosthetic hand 200.

For sake of description, various geometric references are used. A“distal” direction and a “proximal” direction are indicated. As shown,the prosthetic wrist 100 is located proximally relative to theprosthetic hand 200, and the prosthetic hand 200 is located distallyrelatively to the prosthetic wrist 100. The distal and proximaldirections refer to, respectively, directions farther from and closer toa user of the prosthetic system 10 along the length of an arm of theuser containing the prosthetic system 10. A longitudinal axis 12 is alsoindicated. The longitudinal axis 12 is an axis of rotation about whichthe prosthetic wrist 100 and hand 200 rotate. The distal and proximaldirections may be directions along the longitudinal axis 12, for examplewhen the prosthetic system 10 is oriented as shown. “Inner,” “inward,”and like terms refer to directions toward the longitudinal axis 12,while “outer,” “outward,” and like terms refer to directions away fromthe longitudinal axis 12, unless otherwise indicated.

The prosthetic wrist 100 is attached to the prosthetic hand 200 to causemovement of the prosthetic hand 200. A rotatable portion of theprosthetic wrist 100 may be coupled with, for example attached to, theprosthetic hand 200. The rotatable portion of the prosthetic wrist 100rotates, thereby causing rotation of the prosthetic hand 200. Therotatable portion of the prosthetic wrist 100 may include one, some orall of the actuated, e.g. rotated, components of the prosthetic wrist100, as described herein. The prosthetic wrist 100 causes rotation ofthe prosthetic hand 200 relative to an arm, prosthetic or natural, towhich the prosthetic wrist 100 may be attached. The prosthetic wrist 100may be attached to an arm or other components via a fixed portion of theprosthetic wrist 100. The fixed portion of the prosthetic wrist 100 mayinclude one, some or all of the non-actuated, e.g. non-rotated,components of the prosthetic wrist 100, as described herein. In someembodiments, particular components of the fixed portion of theprosthetic wrist 100 may also couple with the prosthetic hand 200, forexample a bearing race that guides rotation of the prosthetic hand 200,as described herein. The rotatable portion of the prosthetic wrist 100may include one, some or all of the actuated, e.g. rotated, componentsof the prosthetic wrist 100, as described herein. The prosthetic wrist100 and hand 200 rotate about the longitudinal axis 12. The prosthetichand 200 may form a plurality of different grips, for example differentpalm and/or digit positions. The prosthetic system 10 may synchronizethe rotation of the prosthetic wrist 100 with the formation of one ofthe grips with the prosthetic hand 200.

Further details of the prosthetic wrist 100 are described herein, forexample with respect to FIGS. 2A-2E. Further details of the prosthetichand 200 are described herein, for example with respect to FIGS. 3A-5B.Further details of prosthetic arms that may be used with the prostheticsystem 10 are described herein, for example with respect to FIGS. 6A-8.Further details of systems and methods for synchronizing rotation of theprosthetic wrist 100 with grip formation of the prosthetic hand 200 aredescribed herein, for example with respect to FIGS. 9-12F.

FIGS. 2A-2E are various views of the prosthetic wrist 100. FIG. 2A is aperspective view of the prosthetic wrist 100. FIG. 2B is a top view ofthe prosthetic wrist 100. FIG. 2C is an exploded view of the prostheticwrist 100. FIG. 2D is a cross-section view of the prosthetic wrist 100taken along the line 2D-2D indicated in FIG. 2B. FIG. 2E is across-section view of the prosthetic wrist of FIG. 1 taken along theline 2E-2E indicated in FIG. 2B.

The prosthetic wrist 100 includes a body 101. The body 101 forms theouter structure of the prosthetic wrist 100. The body 101 may be formedof metals, composites, plastics, polymers, other suitable materials, orcombinations thereof. The body 101 has a generally cylindrical shapeextending along the longitudinal axis 12. The body 101 extends from aproximal end 102 to a distal end 103 of the prosthetic wrist 100. Theproximal end 102 is configured to attach to an arm, such as a natural orprosthetic arm, of a user of the prosthetic system 10. The distal end103 is configured to attach to the prosthetic hand 200.

The prosthetic wrist 100 includes a bearing race 104. The bearing race104 forms a distal end of the body 101. The bearing race 104 is locatedon the distal end 103 of the prosthetic wrist 100. The bearing race 104has a generally circular shape with an opening through the center. Thedistal side of the bearing race 104 is generally flat and abuts acorresponding portion of a prosthetic arm or portion thereof. Theproximal side of the bearing race 104 is generally flat and abuts acorresponding portion of the prosthetic wrist 100. Various fasteningcomponents, such as setscrews, bolts, etc., are attached to the bearingrace 104 to facilitate connection with an arm. The bearing race 104 maybe formed of metals, other suitable materials, or combinations thereof.The bearing race 104 is configured to couple with an arm and withcorresponding components of the prosthetic hand 100. The bearing race104 includes features for rotational connection with the prosthetic hand100. The bearing race 104 guides rotation of the prosthetic hand 100.

The bearing race 104 includes a groove 106. The groove 106 guides therotation of the prosthetic hand 100. The groove 106 is a recessextending circumferentially along an inner side of the bearing race 104.The groove 106 is shaped to receive therein corresponding bearingfeatures that move along the groove 106 as the prosthetic hand 200rotates. The prosthetic wrist 100 may thus include the circular bearingrace 104 located on a distal end of the prosthetic wrist 100 configuredto receive therein, for example in the groove 106, a correspondingbearing component for rotatable connection to the prosthetic hand 200.The groove 106 includes a square or rectangular recess with angledchamfer edges to guide a bearing component, such as a ball, of theprosthetic hand 200 along the length of the groove 106. The groove 106may be or include other shapes, such as semi-circular, etc.

The prosthetic wrist 100 includes a front 108. The front 108 is locateddistally relative to the bearing race 104. The front 108 forms a distalportion of the body 101. The front 108 is generally circular with anopening in the center. The opening of the front 108 has rotatablecomponents of the prosthetic wrist 100 rotating therein. The front 108may be formed of metals, composites, other suitable materials, orcombinations thereof. The distal end of the front 108 surrounds an outerwall of the bearing race 104. The threaded front 108 may thus becircular and attached along an outer circumference of the bearing race104 and extending in the proximal directional. In some embodiments, thefront 108 may attach with or to the bearing 104 in a variety of suitableways, including friction fit, threads, fasteners, adhesive, othersuitable mechanisms, or combinations thereof. A proximal portion of thefront 108 includes a plurality of outer threads 109 along an outercircumferential wall of the front 108. The threads 109 are configured tothreadingly engage with a corresponding proximal component of theprosthetic wrist 100. In some embodiments, there may be one thread 109.In some embodiments, the front 108 may attach with or to the bearing 104in a variety of suitable ways, including threads, friction fit,fasteners, adhesive, other suitable mechanisms, or combinations thereof.

The prosthetic wrist 100 includes a pressure ring 110. The pressure ring110 is an outer band extending circumferentially and forming an outerportion of the body 101. The pressure ring 110 is located proximallyrelative to the bearing race 104 and a portion of the front 108. Thepressure ring 110 surrounds a portion of the front 108 and a portion ofa distal body 122. In some embodiments, the pressure ring 110 may attachwith the front 108 and/or the distal body 122, or other components ofthe prosthetic wrist 100, in a variety of suitable ways, includingfriction fit, fasteners, threads, adhesive, other suitable mechanisms,or combinations thereof. The pressure ring 110 may be relatively thinalong the circumferential length of the pressure ring 110. The pressurering 110 may be formed of a variety of suitable materials, includingmetals, composites, other materials, or combinations thereof. Thepressure ring 110 provides an inward radial force along thecircumference of the pressure ring 110 to various components of theprosthetic wrist 100, such as the front 108 and the distal body 122.

The prosthetic wrist 100 includes an expanding ring 112. The expandingring 112 is an outer structure extending circumferentially to form anouter portion of the body 101 and defines an opening through or near acenter thereof. The expanding ring 112 is located proximally relative tothe pressure ring 110 and bearing race 104 and to portions of the front108 and the distal body 122. The expanding ring 112 includes an inner,circumferential projection along an inner side of the expanding ring112. The expanding ring 112 is circular. The expanding ring 112 may beother shapes, such as non-circular, etc. The expanding ring 112 as shownsurrounds a portion of the distal body 122. The expanding ring 112 mayalso surround other features of the prosthetic wrist, for example thepressure ring 110. The expanding ring 112 sits on an outer projection ofthe distal body 122. In some embodiments, the expanding ring 112 mayattach with the distal body 122, or other components of the prostheticwrist 100, in a variety of suitable ways, including friction fit,fasteners, threads, adhesive, other suitable mechanisms, or combinationsthereof. The expanding ring 112 may be formed of a variety of suitablematerials, including metals, composites, other materials, orcombinations thereof. The expanding ring 112 provides an expansivecircumferential barrier to various components of the prosthetic wrist100, such as the distal body 122 and the pressure ring 110.

The prosthetic wrist 100 includes an actuator module 120. The actuatormodule 120 forms a portion of the body 101. The actuator module 120causes rotation of various components of the prosthetic wrist 100.Rotation of the various components of the prosthetic wrist 100 istransmitted to the prosthetic hand 200 to rotate the prosthetic hand200. The actuator module 120 may include the distal body 122, a proximalbody 124, a stator 125, a longitudinal passageway 126, one or moreproximal bearings 127, one or more heat shrinks 128, a motor 130, arotor 131, one or more central gears 132, and/or one or more peripheralgears 134, as described herein. The actuator module 120 includes themotor 130 that causes rotation of a coupling 150, as described herein.The actuator module 120 is located proximally relative to the bearingrace 104. Various portions of the actuator module 120 are locatedproximally relative to the front 108, the pressure ring 110, and theexpanding ring 112, as described herein.

The distal body 122 is a structural support formed of metals,composites, other suitable materials, or combinations thereof. Thedistal body 122 forms a portion of the body 101 of the prosthetic wrist100. The distal body 122 may include a segmented cross-section extrudedcircularly about the longitudinal axis 112. A distal end of the distalbody 122 is sandwiched in between the front 108 and the pressure ring110. The distal end of the distal body 122 includes inner threads thatengage with the outer threads 109 of the front 108. An outer surface ofthe distal body 122 opposite the threads contacts the inner surface ofthe pressure ring 110. An inner projection of the distal body 122located proximally to the threads of the distal body 122 contacts aproximal surface of the front 108. An outer, angled projection of thedistal body 122 located proximally of the pressure ring 110 contactsinner surfaces of the expanding ring 112 and a distal end of theproximal body 124. In some embodiments, the distal body 122 may supportthe motor 130, as described herein. In some embodiments, the distal body122 may rotatably support various gears, rotors, etc. of the motor 130,as described herein.

The proximal body 124 is a structural support formed of metals,composites, other suitable materials, or combinations thereof. Theproximal body 124 forms a portion of the body 101 of the prostheticwrist 100. The proximal body 124 may include a segmented cross-sectionextruded circularly about the longitudinal axis 112. A distal end of theproximal body 124 surrounds a proximal end of the distal body 122. Theproximal body 124 may attach to or with the distal body 122 withfasteners, adhesive, by friction fit, other suitable mechanisms, orcombinations thereof. An inner ledge of the proximal body 124 extendsradially inward and contacts an outer side of a proximal bearing 127,such as an outer race of the proximal bearing 127. An inner side of theproximal bearing 127, such as an inner race, may therefore rotaterelative to the proximal body 124. The proximal body 124 further extendsproximally from the inner ledge, forming an outer side of the body 101at the proximal end 102 of the prosthetic wrist 100. In someembodiments, the distal body 122 may rotatably support various gears ofthe motor 130, for example the peripheral gears 134, as describedherein.

The stator 125 is a moveable, structural component formed of metals,composites, other suitable materials, or combinations thereof. Thestator 125 has a circular shape with an extended, cylindrical distalportion and a disc-shaped proximal portion having an outer lip. An outersurface of the distal portion of the stator 125 contacts an inner sideof the proximal bearing 127. The stator 125 may therefore rotaterelative to the outer side of the proximal bearing 127 and thus relativeto the proximal body 124. An inner surface of the distal portion of thestator 125 surrounds a heat shrink 128 located at least partially insidethe distal portion of the stator 125. The stator 125 may rotate relativeto the heat shrink 128. An outer side of the distal portion of thestator 125 may be coupled with one or more central gears 132, asdescribed herein. The stator 125 is rotated by the motor 130, forexample by a rotor 131, and transmits rotation to the one or morecentral gears 132.

The stator bearing 127 allows for rotation of the stator 125 relative toother components of the prosthetic wrist 100. The stator bearing 127 maybe a variety of suitable bearing types, including ball bearings, rollerbearings, ball thrust bearings, roller thrust bearings, tapered rollerthrust bearings, or other suitable types. The stator bearing 127, orcomponents thereof such as inner/outer races, retainers, balls, etc.,may be formed from a variety of materials, including metals, ceramics,other suitable materials, or combinations thereof.

The heat shrink 128 separates portions of the stator 125 from otherfeatures of the prosthetic wrist 100 located inside the heat shrink 128.The portions separated by the heat shrink 128 may therefore rotaterelative to each other. The heat shrink 128 may surround a coax holder166 extending through the inner passage of the heat shrink 128, allowingfor rotation of the stator 125 relative to the coax holder 166, asdescribed herein.

The motor 130 is a machine that produces movement. The motor 130 is anelectric motor that produce rotational movement. The motor 130 producesrotation to produce a determined number of Hall Effect pulsescorresponding to the required amount of rotation. The motor 130 may be avariety of suitable types of motors, such as a brushless direct current(DC) motor, a servo motor, a brushed motor, an ultrasonic motor, orother suitable motor types. The motor 130 provides movement to variousportions of the prosthetic wrist 100 that causes rotation of thecoupling 150.

The motor 130 is located proximally relative to the stator 125. Themotor 130 is operatively coupled with the stator 125. The motor 130includes a rotor 130 that is operatively coupled with the stator 125.The motor 130 may include other components operatively coupled with thestator 125. The motor 130 may be rigidly attached to the stator 125 viaone or more shafts. Operation of the motor 130 causes the stator 125 torotate. The motor 130 may be operated in a variety of manners. Angularorientation data is received by the processor 144 of the prostheticwrist 100 and that angular information is calculated into the number ofHall Effect pulses that the motor 130 needs to drive to arrive at thecorrect position. The number of pulses per degree of the prostheticwrist 100 may be about four. Other fewer or greater numbers of pulsesper degree may be implemented. The motor 130 will rotate eitherclockwise or counterclockwise to a target rotational orientationdetermined by the number of pulses to reach the specified angle. Themotor 130 may be operated in a variety of other manners, as described infurther detail herein, for example with respect to FIGS. 9-12F. Thestator 125 may be rigidly attached to the central gear 132, such thatoperation of the motor 130 causes the stator 125 and thus the centralgear 132 to rotate. The rotation of the stator 125 and central gear 132may be about the longitudinal axis 12.

The central gear 132 is a rounded, structural component having featuresfor transmitting rotation. The central gear 132 may be formed of avariety of suitable materials, including metals, plastics, othersuitable materials, or combinations thereof. The central gear 132 iscircular and rotates about the longitudinal axis 12. The central gear132 has teeth along an outer edge that mechanically communicate withcorresponding features of the prosthetic wrist 100, such as one or moreperipheral gears 134. In some embodiments, the central gear 132 may haveother shapes and/or features that mechanically communicate withcorresponding features of the prosthetic wrist 100. There may be one,two, or more central gears 132.

The peripheral gears 134 are rounded, structural components havingfeatures for transmitting rotation. The peripheral gears 134 may beformed of a variety of suitable materials, including metals, plastics,other suitable materials, or combinations thereof. The peripheral gears134 are circular and rotate about axes parallel to the longitudinal axis12. The axes of rotation of the peripheral gears 134 are located in acircular pattern about the longitudinal axis 12. The peripheral gears134 are in mechanical communicate with the central gear 132, the distalbody 122 and the rotator 136. Rotation of the central gear 132 willrotate one or more of the proximal peripheral gears 134, which willrotate the distal body 122, which will rotate the distal proximal gears,which will rotate the rotator 136, and ultimately rotate the coupling150. In some embodiments, the distal body 122 and/or the rotator 136 maybe and/or function as part of the central gear 132 as well. Theperipheral gears 134 have teeth along outer edges that mechanicallycommunicate with corresponding features of the prosthetic wrist 100,such as the central gear 132, the distal body 122 and/or a rotator 136.In some embodiments, the peripheral gears 134 may have other shapesand/or features that mechanically communicate with correspondingfeatures of the prosthetic wrist 100. There may be one, two, three,four, five, six, seven, eight, nine, ten or more peripheral gears 134.The peripheral gears 134 may have outer diameters that are less than,equal to, or greater than outer diameters of the central gear 132. Thus,various gear ratios, mechanical advantages, etc. may be implemented withthe prosthetic wrist 100.

The rotator 136 is a rounded, structural component that transmitsrotation from the peripheral gears 134 to the coupling 150. The rotator136 may be formed of a variety of suitable materials, including metals,plastics, other suitable materials, or combinations thereof. The rotator136 circumferentially surrounds the peripheral gears 134 and extendstherefrom in the distal direction. An inner surface of a proximal, outerportion of the rotator 136 is in mechanical communication with theperipheral gears 134. The rotator 136 rotates about the longitudinalaxis 12 due to rotational forces transmitted from the peripheral gears134. An inner surface of a distal, inner portion of the rotator 136contacts an inner distal bearing 137. An outer surface of a distal,outer portion of the rotator contacts an outer distal bearing 156. Theinner and outer distal bearings 137, 156 may be a variety of suitablebearing types, including ball bearings, roller bearings, ball thrustbearings, roller thrust bearings, tapered roller thrust bearings, orother suitable types. The inner and outer distal bearings 137, 156, orcomponents thereof such as inner/outer races, retainers, balls, etc.,may be formed from a variety of materials, including metals, ceramics,other suitable materials, or combinations thereof. The rotator 136 cantherefore rotate with low friction due to contacts with the inner distalbearing 137 and the outer distal bearing 156. Rotation of the rotator136 is transmitted to the coupling 150, which transmit rotation to theprosthetic hand 200, as described herein.

The prosthetic wrist 100 also includes a motor driver circuit 140,having Hall Effect sensors 142, and a processor 144. An exploded view ofthe prosthetic wrist 100 showing the circuit 140, sensors 142, andprocessor 144 is shown in FIG. 2C. The circuit 140 may be a printedcircuit board (PCB), a printed circuit assembly (PCA), a printed circuitboard assembly or PCB assembly (PCBA), a circuit card assembly (CCA), abackplane assembly, etc. The circuit 140 mechanically supports andelectrically connects various electronic components of the prostheticwrist 100 using conductive tracks, pads and other features etched fromcopper sheets laminated onto a non-conductive substrate. Components suchas capacitors, resistors, sensors, active devices, etc. may be solderedon the circuit 140. The circuit 140 may contain these or othercomponents embedded in the substrate. The circuit 140 may be singlesided (e.g. one copper layer), double sided (e.g. two copper layers) ormulti-layer (e.g. outer and inner layers). In some embodiments, thecircuit 140 may be a printed wiring board (PWB). The circuit 140 islocated adjacent and proximally relative to the motor 130. The circuit140 may detect parameters of the motor 130, for example of the stator131, for analyzing and determining rotations to perform with the motor130, for example with the stator 131. The circuit 140 can be commanded,for example by the processor 144, to drive the motor 130 or portionsthereof. The circuit 140 may include an additional processor in additionto the processor 144.

The circuit 140 includes one or more Hall Effect sensors 142. Thesensors 142 are supported by the circuit 140. The sensors 142 aretransducers that produce varied output voltages in response to amagnetic field. The sensors 142 are used for detecting movement (e.g.speed) and position of magnets or magnetic components of the motor 130,for example of the stator 131. The sensors 142 may operate as analogtransducers, directly returning a voltage due to movement of the stator131. With a known magnetic field, the distance between correspondingmagnets of the stator 131and sensors 142 can be determined. Usingmultiple sensors 142, the relative position of the magnets and thus ofthe stator 131can be determined. The sensors 142 can acts as switches.For example, threshold distances between the magnets of the stator 13land the sensors 142 can be detected. The sensors 142 may be used todetect the position of one or more permanent magnets of the stator 131,for example to analyze and control the speed, position, etc. of thestator 131. Data from the sensors 142 can be communicated to theprocessor 144 to drive the stator 131.

The processor 144 is located proximally relative to the circuit 140. Theprocessor 144 may be a specialized microprocessor such as a digitalsignal processor (DSP). The processor 144 measures, filters and/orcompresses signals from the various sensors and devices. The processor144 is in electrical communication with the circuit 140, sensors 142 andthe motor 130. The processor 144 is also in electrical communicationwith sensors of the prosthetic hand 200, such as an IMU, as describedherein. The processor 144 may also be in electrical communication withexternal control devices, such as mobile devices like phones andwearables, as described herein. The processor 144 analyzes data,signals, etc. received from the various sensors and devices, anddetermines commands for driving the motor 130 via the circuit 140. Theprocessor 144 communicates data with the circuit 140 and/or theadditional processor of the circuit 140, which data may regard, forexample, speed, direction and position of the motor 130 or portionsthereof. Driving the motor 130 causes the coupling 150 to rotate, asdescribed herein, thereby rotating the prosthetic hand 200.

The prosthetic wrist 100 includes the coupling 150. The coupling 150 isa structural connector that is configured to rotatably couple theprosthetic wrist 100 with the prosthetic hand 200. The coupling 150includes a circular base 151 coupled with one or more teeth 152extending in the distal direction from the base 151. The teeth 152 arelocated at or near a periphery or outer edge of the base 151. The teeth152 are in a circular pattern. The base 151 and teeth 152 may be formedfrom a variety of materials, including metals, plastics, composites,other suitable materials, or combinations thereof. The base 151 definesan opening 154 through or near the center of the base 151. The base 151may include holes or other features around the opening 154 for attachingthe coupling to the rotator 136. The coupling 150 may be connected tothe rotator 136 with fasteners, adhesives, other suitable mechanisms, orcombinations thereof. An outer, proximal portion of the base 151contacts the outer distal bearing 156. Thus the coupling 150 may rotatewith the rotator 136 and be guided by the outer distal bearing 156. Thecoupling 150 and rotator 136 may contact the same inner race of theouter distal bearing 156. A portion of the coupling 150 may sit on adistal portion of the outer distal bearing 156.

The proximal end of the coupling 150 is shown rigidly connected to therotator 136. Rotation of the rotator 136 thus causes the coupling 150 torotate. The distal end of the coupling 150 is configured to couple withthe prosthetic hand 200. With the prosthetic hand 200 connected to thecoupling 150, rotation of the coupling 150 is thus transmitted to theprosthetic hand 200. The coupling 150 may connect with the prosthetichand 200 in a number of configurations. For example, the teeth 152 maycontact, either fixedly or passively, corresponding features of theprosthetic hand 200 that can be positioned between the teeth 152, asdescribed herein. The coupling 150 may removably connect with theprosthetic hand 200, for example by friction fit, such that a thresholdforce applied to the prosthetic hand 200 in the distal direction and/ora threshold force applied to the prosthetic wrist 100 in the proximaldirection will disconnect the coupling 150 from the correspondingfeatures of the prosthetic hand 200. The coupling 150, bearing race 104and other features may allow for a simple, quick and easy disconnect ofthe prosthetic hand 200 from the prosthetic wrist 100, as furtherdescribed herein.

The prosthetic wrist 100 includes a coaxial assembly 160. The coaxialassembly 160 provides a wired transmission of electrical communicationbetween the prosthetic wrist 100 and the prosthetic hand 200. Thecoaxial assembly 160 includes a plug 162, a circuit 164, a holder 166and one or more cables 168. The plug 162 extends in the distal directionthrough and away from the coupling 150. The plug 162 is configured toconnection to corresponding features of the prosthetic hand 100, such asa coaxial socket. The plug 162 is rounded and extends distally along thelongitudinal axis 12 with a portion thereof protruding slightly beyondthe bearing race 104 in the distal direction. The plug 162 includesconductive connections for electrically connecting with the prosthetichand 200. The plug 162 may be rotationally stationary about thelongitudinal axis 12 but allow for rotation of the prosthetic hand 200about the plug 162 while maintaining electrical communication betweenthe prosthetic wrist 100 and prosthetic hand 200.

The circuit 164 and cables 168 are in electrical communication with theplug 162. The circuit 164 may be a printed circuit board (PCB), or othertypes of suitable circuits. The circuit 164 may be in wired connectionwith the plug 162 and the cables 168. The circuit 164 may receive and/ortransmit electrical signals from and/or to the plug 162 and cables 168.The circuit 164 is located proximally relative to the plug 162. Thecables 168 extend in a proximal direction from the circuit 164. Thecable 168 is a communication cable capable of transmitting data,information etc. The coaxial assembly 160 may include multiple cables168. As shown, there are four cables 168. In some embodiments, thecoaxial assembly 160 or portions thereof may not be necessary, forexample the prosthetic hand 200 may be entirely or partially in wirelesscommunication with the prosthetic wrist 100.

The holder 166 supports the one or more cables 168. The holder 166 is anelongated structural support extending through the passageway 126. Adistal end of the holder 166 extends to the circuit 164. A proximal endof the holder 166 extends to the motor driver circuit 140. The circuit140 may support the proximal end of the holder 166. The holder 166 mayhave a generally planar shape as shown. The holder 166 may be formedform a variety of materials, including plastics, polymers, othersuitable materials, or combinations thereof.

The prosthetic wrist 100 includes a proximal cover 170. The proximalcover 170 is a structural end piece. The proximal cover 170 is roundedand connects with the proximal body 124. The cover 170 may in additionor alternatively connect with other features of the prosthetic wrist100, such as the processor 144. The proximal cover 170 may connect withthe various features by fasteners, threads, friction fit, adhesives,other suitable mechanisms, or combinations thereof. The proximal cover170 may cover and protect the processor 144. The processor 144 may bedisposed inside the proximal cover 170. The proximal cover 170 may alsofacilitate attachment with various features of other prostheticcomponents, such as prosthetic arms, as described herein.

The features of the prosthetic wrist 100 described herein relate tomerely some embodiments of the prosthetic wrist 100. Other embodimentsof the prosthetic wrist 100 and features thereof not explicitlydescribed herein are within the scope of the present disclosure. In someembodiments, the prosthetic wrist 100 is configured to rotate about morethan on axis. For example, the prosthetic wrist 100 may be configured torotate about the longitudinal axis 12 and about one or more axesperpendicular to the longitudinal axis 12. An example X-Y-Z axis systemis shown in FIG. 1, where the X axis is parallel to the longitudinalaxis 12. Further indicated are roll, pitch and yaw rotations about,respectively, the X axis, Y axis and Z axis. The rotations may be in thedirections indicated or in the opposite direction. The prosthetic wrist100 may be configured to perform any combination of such rotations(roll, pitch and yaw), such as roll and pitch, roll and yaw, or roll,pitch and yaw. Further, the various embodiments of the prosthetic wrists100 may be used with a multitude of embodiments of prosthetic hands.Some embodiments of such prosthetic hands are described herein withrespect to the prosthetic hand 200. The prosthetic hand 200 may also beconfigured to perform various rotations. In some embodiments, theprosthetic hand 200 may be configured to perform any combination of theroll, pitch and yaw rotations, such as only pitch, only yaw, roll andpitch, roll and yaw, or roll, pitch and yaw. In some embodiments, wristflexion and/or wrist deviation may be performed, e.g. pitch of the wristin both rotational directions. The prosthetic hand 200 and/or theprosthetic wrist 100 may be configured to perform such rotations. Insome embodiments, separate components may be incorporated with theprosthetic hand 200 and/or the prosthetic wrist 100 to perform suchrotations. For example, a separate device in between the prosthetic hand200 and the prosthetic wrist 100 may perform such rotations.

FIG. 3A is a perspective view of the prosthetic hand 200. FIGS. 3B-3Gare various views of the prosthetic hand 200 with some componentsremoved for clarity. FIG. 3H is a bottom perspective view and FIG. 31 isa bottom view of the prosthetic hand 200. The geometric references“distal” and “proximal” directions are indicated for sake ofdescription. The longitudinal axis 12 is indicated as shown. Theprosthetic hand 200 connects to and is rotated by the prosthetic wrist100. The prosthetic hand 200 may rotate about the longitudinal axis 12.The prosthetic hand 200 is capable of forming a multitude of grips, forexample various orientations of one or more digits and/or a palm. Theprosthetic hand 200 may form such grips in sync with rotation of theprosthetic hand 200, as described herein. The prosthetic hand 200described herein is merely an example of a prosthetic hand that may beimplemented. Other prosthetic hands may be implemented, for example asdescribed in U.S. Pat. No. 8,696,763,titled PROSTHETIC APPARATUS ANDCONTROL METHOD and issued on Apr. 15, 2014, the entire contents of whichare incorporated by reference herein for all purposes.

The prosthetic hand 200 includes a wrist attachment 204. The wristattachment 204 may be a quick wrist disconnect (QWD) device, allowingfor quick connection to and/or quick disconnection from the prostheticwrist 100. The wrist attachment 204 is a structural connector on theproximal end of the prosthetic hand 200. The wrist attachment 204includes a ball bearing retainer 206 having one or more ball bearings208 contained therein. The ball bearing retainer 206 extends in thedistal direction and is configured to be received by the prostheticwrist 100. The ball bearing retainer 206 may be received within thebearing race 104 of the prosthetic wrist 100. The ball bearings 208 maybe received into the groove 106 of the bearing race 104. The ballbearings 208 may rotate within the groove 106 as the prosthetic hand 200is rotated by the prosthetic wrist 100. The ball bearing retainer 206and ball bearings 208 may form a variety of different bearing types,including ball bearings, roller bearings, ball thrust bearings, rollerthrust bearings, tapered roller thrust bearings, or other suitabletypes. The ball bearing retainer 206 and ball bearings 208 may be formedfrom a variety of materials, including metals, ceramics, other suitablematerials, or combinations thereof.

The wrist attachment 204 includes a locking ring 210 having a series ofprojections 211 (see FIGS. 3H and 31) for connecting to the coupling150. The locking ring 210 is a rounded structure coupled with the wristattachment 204. The locking ring 210 may be coupled with, for exampleattached directly to, the ball bearing retainer 206. The locking ring210 engages with the coupling 150 of the prosthetic wrist 100. Theprojections 211 may be complementary structures that correspond to andfit in between the teeth 152 of the coupling 150. The projections 211are raised, triangular portions of the locking ring 210 definingrectangular spaces therebetween into which the teeth 152 are received.The projections 211 and/or spaces defined thereby may have other shapes.

Rotation of the coupling 150 transmits rotation to the wrist attachment204 via the teeth 152 and projections 211. When engaged together, theprojections 211 may passively contact the teeth 152 such that lateral orcircumferential movement of the projections 211 relative to the teeth152 is inhibited by the teeth 152. When engaged together, theprojections 211 may not be inhibited by the teeth 152 from movingaxially in the distal direction away from the teeth 152. The base 152may inhibit axial movement of the projections 211 in the proximaldirection. The bearing race 104, such as the groove 106, may alsoprevent axial movement of the ball bearings 208 and thus of theprosthetic hand 200 in the proximal and/or distal directions.

The prosthetic hand 200 includes a palm assembly 212 connected to fourprosthetic finger digits 240 and one prosthetic thumb digit 280. Thepalm assembly 212 is a structural assembly forming a palm portion of theprosthetic hand 200. The palm assembly 212 includes a hand chassis 214having one or more chassis walls 216. FIG. 3B is a palm-side view andFIG. 3C is a back-side view of the prosthetic hand 200. “Palm-side” andback-side are used here in their ordinary sense with respect to naturalhands. Both FIGS. 3B and 3C have some features removed for clarity, forexample to see interior components of the prosthetic hand 200.

The hand chassis 214 is a structural support for various features of theprosthetic hand 100. The walls 216 extend in various directions tosupport such features. Walls 216 at the proximal end of the hand chassis214 connect to the wrist attachment 204. The hand chassis 214 may beconnected to the wrist attachment 204 with fasteners, threads, othersuitable mechanisms, or combinations thereof. The walls 216 may extendin the distal direction to a distal end of the palm assembly 212.

The walls 216 at the distal end of the hand chassis 214 connect to oneor more knuckle blocks 218. The knuckle blocks 218 are structuralconnectors that connect the palm assembly 212 to the prosthetic fingerdigits 240. The prosthetic thumb digit 280 may similarly attach to athumb knuckle block on the thumb-side of the palm assembly 212. Furtherdetails of the prosthetic finger digits 240 and the prosthetic thumbdigit 280 are described herein, for example with respect to FIGS. 4A-4Band FIG. 5A-5B respectively.

The prosthetic hand 200 includes a motor assembly 220 and thumb rotator222. The motor assembly 220 and thumb rotator 222 may be part of thepalm assembly 212. The motor assembly 220 causes movement, for examplerotation, of the prosthetic thumb digit 280 via the thumb rotator 222.The motor assembly 220 may include an electric motor for causing suchmovement. The motor assembly 220 may include a variety of suitable typesof motors, such as a brushless direct current (DC) motor, a servo motor,a brushed motor, an ultrasonic motor, or other suitable motor types. Thethumb rotator 222 may transmit movement from the motor assembly 220 tothe prosthetic thumb digit 280. The motor assembly 220 and thumb rotator222 may cause the prosthetic thumb digit 280 to rotate about one or moreaxes.

The prosthetic hand 200 includes a dorsal fairing 224 (see FIG. 6B) anda palm fairing 226. The dorsal fairing 224 is located on the dorsal orback-side of the prosthetic hand 200. An outer side of the dorsalfairing 224 faces in a dorsal direction when attached to the prosthetichand 200, forming a back-side of the prosthetic hand 200. The palmfairing 226 is located on the palm-side of the prosthetic hand 200opposite the dorsal fairing 224. An outer side of the palm fairing 226faces in a palm direction when attached to the prosthetic hand 200,forming a palm side of the prosthetic hand 200. In FIG. 3B, the palmfairing 226 has been removed for clarity. In FIG. 3C, the dorsal fairing224 has been removed for clarity. The dorsal and palm fairings 224, 226are structural covers of the prosthetic hand 200. The dorsal and palmfairings 224, 226 may be formed of composites, plastics, polymers,metals, other suitable materials, or combinations thereof. The dorsaland palm fairings 224, 226 may be fastened to the prosthetic hand 200,for example to the hand chassis 214 or walls 216 thereof. The dorsal andpalm fairings 224, 226 may, in addition or alternatively, be attached tothese or other features of the prosthetic hand 200 with a variety ofother suitable mechanisms.

The prosthetic hand 200 defines a cavity 228. The cavity 228 may beinside the palm assembly 212. The cavity 228 is formed at least in partby the dorsal and palm fairings 224, 226. The cavity 228 may containvarious features of the prosthetic hand 200, such as the hand chassis214, the motor assembly 220 and associated motor, the thumb rotator 222,the knuckle blocks 218, the thumb knuckle block, and/or other features.

The prosthetic hand 200 includes an inertial measurement unit (IMU) 230.The IMU 230 is an electronic device that detects and communicatesvarious parameters related to the orientation of the IMU 230 and thus ofthe prosthetic hand 200. The IMU 230 may measure accelerations and/orspeeds (i.e. rates), which may be linear and/or angular. The IMU 230 maymeasure magnetic fields. The IMU 230 may incorporate one or moreaccelerometers, gyroscopes, and/or magnetometers. The IMU 230 as shownis a nine-axis IMU, including a three-axis accelerometer, a three-axisgyroscope, and a three-axis magnetometer.

The prosthetic hand 200 includes one IMU 230. In some embodiments, theprosthetic hand 200 may include multiple IMUs 230. As shown in FIG. 3C,the IMU 230 is located on a back-side of the prosthetic hand 200,connected to a back-side of the hand chassis 214. The IMU 230 may belocated in various positions of the prosthetic hand 200 and attached invarious manners, for example depending on the size, type, etc. of theprosthetic hand 200. Additional embodiments of the prosthetic hand 200showing alternative locations of the IMU 230 are shown in FIGS. 3D-3G.FIG. 3D is a back-side view with the dorsal fairing 224 removed, andFIG. 3E is a palm-side view, of a relatively smaller prosthetic hand 200including the IMU 230 orientated horizontally. FIG. 3F is a back-sideview with the dorsal fairing 226 removed, and FIG. 3G is a palm-sideview with part of the palm fairing 226 removed, of a relatively largerprosthetic hand 200 including the IMU 230 orientated vertically. FIGS.3D and 3F do not include the prosthetic thumb digit 280 for clarity.

The IMU 230 detects one or more accelerations, one or more rates ofmovement and magnetic field strengths in one or more directions todetermine an orientation of the prosthetic hand 230 in three-dimensionalspace. The IMU 230 as shown detects accelerations along three orthogonaldirections, rates of movement along three orthogonal directions, andmagnetic field strength along three orthogonal directions. The IMU 230may detect the accelerations, rates and magnetic field strengths alongthe same three orthogonal directions. In some embodiments, the IMU 230may detect the accelerations, rates and magnetic field strengths alongdifferent directions. The IMU 230 may communicate the detectedparameters to other features of the prosthetic hand 200 and/or to theprosthetic wrist 100. The IMU 230 may communicate the detectedparameters to the processor 144 of the prosthetic wrist 100. The IMU 230may communicate the detected parameters to a communications deviceassociated with the processor 144. The IMU 230 may communicate thedetected parameters to other devices, electronics, etc. of theprosthetic wrist 100. The IMU 230 may communicate the detectedparameters to a processor, communications device, circuit, or otherelectronics of the prosthetic hand 200. In some embodiments, the IMU 230may perform calculations based on the detected parameters andcommunicate the results of those calculations to the aforementioneddevices.

The prosthetic hand 200 includes a circuit 231 and processor 233. Theprosthetic hand 200 may also include a speed boost circuit 232. Thecircuits 231, 232 are a printed circuit boards (PCB) in electricalcommunication with the processor 233. The circuit 231 is incommunication with the processor 233 and the IMU 230. The circuit 231may be a variety of suitable types of electronic circuits. The processor233 may be a variety of suitable types of processors, including thosedescribed with respect to the processor 144 of the prosthetic wrist 100.The circuit 231 and/or processor 233 are in electrical communicationwith the various electronics of the prosthetic hand 200, including themotor assembly 220, the IMU 230, the prosthetic finger digits 240 and/oractuators thereof, the prosthetic thumb digit 280 and/or actuatorsthereof, one or more batteries, and other devices. The processor 233measures, filters and/or compresses signals from the various sensors anddevices of the prosthetic hand 200 and controls movement of theprosthetic hand 200, for example movement of the prosthetic fingerdigits 240 and/or the prosthetic thumb digit 280. The circuit 231 and/orprocessor 233 may receive EMG signals and drive the prosthetic digits240, 280 via an H bridge circuit chip, e.g. one H bridge circuit chipfor each of the prosthetic digits 240, 280. The circuit 231 and/orprocessor 233 may be in communication with one or more grip chips, asdescribed herein. The grip chips may be electronic sensors placed at ornear items where particular grips are desirable. Different particulargrip chips may be used for various items, such as a “cup” grip chipplaced near cups, so that the prosthetic hand 200 forms a grip to hold acup when the prosthetic hand 200 is within proximity of the “cup” gripchip. This is merely one example and other suitable grip chips may beused

The speed boost circuit 232 may be a speed boost PCB. The speed boostcircuit 232, for example the speed boost PCB, may increase an inputvoltage enabling the prosthetic digits to move, for example rotate, at afaster rate, acceleration, etc. The speed boost circuit 232 includes anon-off switch 236 that protrudes through an opening 238 of the palmfairing. The on-off switch 236 can be toggled to power the electronicsof the prosthetic hand 200 on and off. The on-off switch 236 can alsocontrol powering the prosthetic wrist 100 on and off, for example viathe coaxial assembly 160.

The prosthetic hand 200 can form various grips. The prosthetic fingerdigits 240 and prosthetic thumb digit 280 may actuate, for examplerotate, to form the grips. In some embodiments, the palm assembly 212can rotate, for example along the longitudinal axis 12 and/or alongother axes. The formation of various grips with the prosthetic hand 200is performed in sync with the wrist rotation by the prosthetic wrist100. The prosthetic finger digits 240 and prosthetic thumb digit 280actuate based on commands sent to various actuators, as describedherein.

FIG. 4A is a perspective view of one of the prosthetic finger digits 240of the prosthetic hand 100. FIG. 4B is a side view of the prostheticfinger digit 240 with some components removed for clarity. FIG. 4C is aside cross-section view of the prosthetic finger digit 240 showing awire 265 and spring 267 for rotating outer portions of the prostheticfinger 240. The prosthetic finger digits 240 may have the same orsimilar features and/or functionalities as each other. The prostheticfinger digits 240 may be different sizes, for example to mimic naturalfinger sizes or to accommodate smaller or larger prosthetic hands 200.The following description may apply to all of the prosthetic fingerdigits 240 regardless of these variations in size. The prosthetic fingerdigits 240 and components thereof may be formed of plastic, metal,composite, other suitable materials, or combinations thereof

The prosthetic finger digit 240 includes a finger knuckle assembly 244.The finger knuckle assembly 244 is a structural attachment forconnecting the prosthetic finger digit 240 to the prosthetic hand 200,for example to the hand chassis 214. A worm wheel 246 is attached to thefinger knuckle assembly 244. The worm wheel 246 includes a body 247having a rounded edge 248. The worm wheel 246 is a structural componentfor guiding movement of the prosthetic finger digit 240. The contour ofthe rounded edge 248 may provide a guide path for advancement of theprosthetic finger digit 240 along the rounded edge 248 along the twodirections indicated by the geometric reference double-sided arrow 250.Advancement of the prosthetic finger digit 240 causes rotation about ahole 249 of the worm wheel 246. The rotation may be in two directions,as indicated by the geometric reference double-sided arrow 263. The hole249 is configured to receive a pivot pin 262 therein, as describedherein, to facilitate rotation. The rounded edge 248 includes a seriesof teeth (not shown) configured to engage with a worm gear helix 258, asdescribed herein, that guide the prosthetic finger digit 240 along therounded edge 248.

The prosthetic finger digit 240 includes a gearbox 252. The gearbox 252is removed for clarity in FIG. 4B. The gearbox 252 is rotatably attachedto the finger knuckle assembly 244 and worm wheel 246 via the pivot pin262. The gearbox 252 contains various actuation devices and accessoriesfor moving the prosthetic finger digit 240. The gearbox 252 includes amotor 254, motor bearing 256 and worm gear 257. The motor 254 actuatesto cause the rotation of the prosthetic finger digit 240 about the pivotpin 262. The motor 254 may be a variety of suitable motors, includingelectric, brushless, etc. The motor bearing 256 is contacted on thedistal side by the motor 254 and on the proximal side by the worm gear257. The proximal end of the worm gear 257 contacts a worm bearing 260.The motor 254 causes the worm gear 257 to rotate. As the worm gear 257rotates, a helix 258 of the worm gear 257 engages with the teeth of theworm wheel 246. Engagement of the helix 258 causes the worm gear 257 toadvance along the rounded edge 248 of the worm wheel 246, causing thegearbox 252 portion of the prosthetic finger digit 240 to rotate aboutthe pivot pin 262 in a first direction indicated by the arrow 263. Themotor 254 can be reversed to cause rotation of the prosthetic fingerdigit 240 to rotate about the pivot pin 262 in a second directionindicated by the arrow 263 that is opposite the first direction. Theremay be no axial play between the motor bearing 256, the helix 258, theworm gear 257, the worm bearing 260 and/or the motor 254 when assembledtogether as shown.

The prosthetic finger digit 240 includes a fairing 264 attached to theprosthetic finger digit 240 that covers part of the gearbox 252. Thefairing 264 may be moveable or stationary. The fairing 264 may berotatably connected, for example with the pivot pin 262. A knuckle capthinner 266 is attached to a distal end of the gearbox 252. The knucklecap thinner 266 extends in the distal direction and is rotatablyconnected to a retaining tab thinner 268.

The retaining tab thinner 268 can rotate relative to the knuckle capthinner 266 in the two opposite directions indicated by the double-sidedarrow 269. Rotation of the retaining tab thinner 268 may be passive, forexample caused by rotation of the gearbox 252 about the pivot pin 262.In some embodiments, the wire 265 (shown in FIG. 4C) connects toportions of the prosthetic finger 240 located distally of the knucklecap thinner 266, for example to the retaining tab thinner 268. The wire246 extends from one or more proximal portions of the prosthetic finger240, such as the worm wheel 246 as shown, to one or more distal portionsof the prosthetic finger 240, such as the gearbox 252 and retaining tabthinner 268, and/or the fingertip assembly 270. The wire 246 may extendalong or around one or more hinge points as shown. The wire 246 may begenerally inelastic. The wire 246 may be a nylon monofilament cable,such as gorilla wire. Rotation of the gearbox 252 about the pivot pin262 may pull on, e.g. increase tension in, the wire 265 thus pulling onthe retaining tab thinner 268 and/or the fingertip assembly 270 andcausing the retaining tab thinner 268 and fingertip assembly 270 torotate in a first direction indicated by the arrow 269 such that theprosthetic finger digit 240 closes. By “closes” it is meant that theprosthetic finger 240 as oriented in FIG. 4B rotates at least partiallyin the counterclockwise directions at the arrows 262 and 269. Asoriented in FIG. 4C, closing of the prosthetic finger 240 is rotation inthe clockwise direction. Closing the prosthetic finger 240 may pull onand expand the spring 267 (shown in FIG. 4C), thus providing an openingforce that acts against the closing force provided by the wire 265. Thespring 267 may be a tension spring, coil spring, or other suitable typesof springs. The spring 267 may provide a compressive force whenexpanded. Rotation of the gearbox 252 about the pivot pin 262 mayprovide more slack to, e.g. decrease tension in, the wire 265 allowingthe spring 267 to pull on the retaining tab thinner 268 to rotate theretaining tab thinner 268 in a second direction indicated by the arrow269 that is opposite to the first direction such that the prostheticfinger digit 240 opens. By “opens” it is meant that the prostheticfinger 240 as oriented in FIG. 4B rotates in the clockwise directions atthe arrows 262 and 269. As oriented in FIG. 4C, opening of theprosthetic finger 240 is rotation in the counterclockwise direction.Thus, “closed” and “opened” here refer to their ordinary meaning of anatural hand being opened, for example with an opened hand with straightfingers, or closed, for example a closed fist with curled fingers.

The rotation of the outer segments of the prosthetic finger digit 240,such as the retaining tab thinner 268, may therefore be proportional(e.g. linearly related) to rotation of the inner segments, such as thegearbox 252. In some embodiments, other mechanisms for rotation of theouter segments of the prosthetic finger digit 240 may be implemented.For example, the retaining tab thinner 268 or other segments may berotated by a separate motor. Thus, the particular configuration and gripformation means of the prosthetic hand 200 described herein are merelysome example embodiments, and other suitable configurations and gripformation means may be implemented.

A fingertip assembly 270 is rigidly attached to a distal end of theretaining tab thinner 268. The fingertip assembly 270 includes a fingerextension 272 and a fingertip 274. A proximal end of the fingerextension 274 is attached to a distal end of the retaining tab thinner268. A proximal end of the fingertip 274 is attached to a distal end ofthe finger extension 272. In some embodiments, the elastic member thatcauses rotation in the directions along arrow 269 may be connected tothe fingertip assembly 270.

The rotation of the various segments of the prosthetic finger digit 240may be performed to form various grips with the prosthetic hand 200. Forsome grips, the prosthetic finger digits 240 may be rotated differentamounts at the respective joints of each prosthetic finger digit 240.For some grips, the prosthetic finger digits 240 may be rotated the sameamounts at the respective joints of each prosthetic finger digit 240.For some grips, some of the prosthetic finger digits 240 may be rotatedthe same amounts while other prosthetic finger digits 240 may be rotateddifferent amounts at the respective joints. For example, the prosthetichand 200 shown in FIG. 6B has one of the prosthetic finger digits 240straight while the others are curved. Many other grips are possible.Further details of an example grip formation are described herein, forexample with respect to FIGS. 12A-12F. The movement of the prostheticthumb digit 280 may also contribute to various grip formations.

FIG. 5A is a perspective view of the prosthetic thumb digit 280. FIG. 5Bis a side view of the prosthetic finger digit 280 with some componentsremoved for clarity. The prosthetic thumb digit 280 may be differentsizes, for example to accommodate smaller or larger prosthetic hands200. The following description of the prosthetic thumb digit 280 mayapply regardless of these variations in size. The prosthetic thumb digit280 and components thereof may be formed of plastic, metal, composite,other suitable materials, or combinations thereof.

The prosthetic thumb digit 280 includes a thumb knuckle assembly 282.The thumb knuckle assembly 282 is a structural attachment for connectingthe prosthetic thumb digit 280 to the prosthetic hand 200, for exampleto the hand chassis 214. A worm wheel 284 is attached to the thumbknuckle assembly 282. The worm wheel 284 includes a body 285 having arounded edge 286. The worm wheel 284 is a structural component forguiding movement of the prosthetic thumb digit 280. The contour of therounded edge 286 may provide a guide path for advancement of theprosthetic thumb digit 280 along the rounded edge 286 along the twodirections indicated by the geometric reference double-sided arrow 287.Advancement of the prosthetic thumb digit 280 causes rotation about ahole 288 of the worm wheel 284. The rotation may be in two directions,as indicated by the geometric reference double-sided arrow 289. The hole288 is configured to receive a pivot pin 296 therein, as describedherein, to facilitate rotation. The rounded edge 286 includes a seriesof teeth (not shown) configured to engage with a worm gear helix 294, asdescribed herein, that guide the prosthetic thumb digit 280 along therounded edge 286.

The prosthetic thumb digit 280 includes a gearbox 290. The gearbox 290is removed for clarity in FIG. 5B. The gearbox 290 is rotatably attachedto the thumb knuckle assembly 282 and worm wheel 284 via the pivot pin296. The gearbox 290 contains various actuation devices and accessoriesfor moving the prosthetic thumb digit 280. The gearbox 252 includes amotor 291, motor bearing 292 and worm gear 293. The motor 291 actuatesto cause the rotation of the prosthetic thumb digit 280 about the pivotpin 296. The motor 291 may be a variety of suitable motors, includingelectric, brushless, etc. The motor bearing 292 is contacted on thedistal side by the motor 291 and on the proximal side by the worm gear293. The proximal end of the worm gear 293 contacts a worm bearing 299.The motor 291 causes the worm gear 293 to rotate. As the worm gear 293rotates, a helix 294 of the worm gear 293 engages with the teeth of theworm wheel 284. Engagement of the helix 294 causes the worm gear 293 toadvance along the rounded edge 286 of the worm wheel 284, causing thegearbox 290 portion of the prosthetic thumb digit 280 to rotate aboutthe pivot pin 296 in a first direction indicated by the arrow 289. Themotor 291 can be reversed to cause rotation of the prosthetic thumbdigit 280 to rotate about the pivot pin 296 in a second directionindicated by the arrow 289 that is opposite the first direction.

The prosthetic thumb digit 280 includes a thumb fairing 297 and fixedfairing 298 attached to the prosthetic thumb digit 280 that cover partof the gearbox 290. The thumb fairing 297 may be connected to the pivotpin 296. The thumb fairing 297 is moveable, for example rotatable aboutthe pivot pin 296. The fixed fairing 298 may be connected to the palmassembly 212, for example the hand chassis 214. The fixed fairing 298may be stationary. A thumb tip 299 is attached to a distal end of thegearbox 290. The thumb tip 299 may be rigidly attached to the gearbox290. In some embodiments, the thumb tip 299 may be moveable, for examplerotatable, relative to the gearbox 290.

The prosthetic thumb digit 280 can rotate relative to the palm assembly212. The prosthetic thumb digit 280 is rotatable in the two directionsindicated by the arrow 289. The prosthetic thumb digit 280 is rotatableto “open” and “close” as described above. For example, the prostheticthumb digit 280 can rotate counterclockwise as oriented in FIG. 5B, forinstance when closing the prosthetic thumb digit 280 and/or forming aclosed grip with the prosthetic hand 200. For example, the prostheticthumb digit 280 can rotate clockwise as oriented in FIG. 5B, forinstance when opening the prosthetic thumb digit 280 and/or forming anopen grip with the prosthetic hand 200.

The rotation of the prosthetic thumb digit 280 may be performed to formvarious grips with the prosthetic hand 200. For some grips, theprosthetic thumb digit 280 may be rotated the same or different amountscompared to some or all of the prosthetic finger digits 240. Many gripsare possible. Further details of an example grip formation are describedherein, for example with respect to FIGS. 12A-12F.

FIG. 6A is a perspective view of the prosthetic wrist 100 attached to anembodiment of a prosthetic lower arm 300. The prosthetic lower arm 300is a prosthetic for the lower or outer segment of an arm, for examplethe forearm. The prosthetic lower arm 300 is a hollow tube with anarm-like shape. The prosthetic lower arm 300 may have a variety of othersuitable shapes and configurations. The proximal end of the prostheticlower arm 300 attaches to a user, for example to a stump of an amputee,a fitting, socket, etc. The distal end of the prosthetic lower arm 300attaches to the prosthetic wrist 100. The prosthetic lower arm 300 maybe mechanically and/or electrically connected to the prosthetic wrist100. The prosthetic lower arm 300 receives the prosthetic wrist 100through an opening at the distal end of the prosthetic lower arm 300. Insome embodiments, the prosthetic wrist 100 when attached to theprosthetic lower arm 300 may not be entirely inside the prosthetic lowerarm 300. For example, the prosthetic wrist 100 when attached to theprosthetic lower arm 300 may be partially, mostly, or entirely outsidethe prosthetic lower arm 300. Thus, the example configuration shown ofattachment of the prosthetic wrist 100 to the example embodiment of theprosthetic lower arm 300 is merely one possible configuration, and manyother suitable configurations may be implemented. Further, theprosthetic wrist 100 can connect to the prosthetic lower arm 300 in anumber of suitable manners. For example, the body 102, the actuatormodule 120, the proximal body 124, the circuit 140, the processor 144,the proximal cover 170, portions thereof, and/or other features of theprosthetic wrist 100 may attach to the prosthetic lower arm 300.

FIG. 6B is a perspective view of the prosthetic lower arm 300 having theprosthetic wrist 100 installed therein, with the prosthetic hand 200shown detached from the prosthetic wrist 100. The prosthetic system 10may therefore be used with the prosthetic lower arm 300. The prosthetichand 200 may be attached to the prosthetic wrist 100, thereby forming acomplete prosthetic lower arm, wrist and hand system. The prosthetichand 200 may be attached to the prosthetic wrist 100 by moving theprosthetic hand 200 in the proximal direction along the longitudinalaxis 12. The prosthetic hand 200 may be detached from the prostheticwrist 100 by moving the prosthetic hand 200 in the distal directionalong the longitudinal axis 12. When attached together, the prostheticlower arm 300 and prosthetic wrist 100 may be aligned with thelongitudinal axis 12, as shown. When attached to the prosthetic wrist100, the prosthetic hand 200 may rotate about the longitudinal axis 12as indicated, while the prosthetic lower arm 300 remains rotationallystationary. Thus, the prosthetic hand 200, when attached to theprosthetic wrist 100, may rotate about the longitudinal axis 12 relativeto the prosthetic lower arm 300. The rotation of the prosthetic hand 200is caused by the prosthetic wrist 100, as described herein.

FIG. 6C is a perspective view of the prosthetic wrist 100 attached tothe lower arm prosthetic 300. The lower arm prosthetic 300 istransparent for clarity. The lower arm prosthetic 300 includes anelectromyography (EMG) system 180. The EMG system 180 is configured toread EMG signals from a user of the prosthetic system 10. The EMG system180 may be used to control the prosthetic system 10, for example toenter a gesture control mode, as described herein.

The EMG system 180 includes a processor 182 in electrical communicationwith the prosthetic wrist 100 via one or more wires 184. In someembodiments, the processor 182 may be connected wirelessly to theprosthetic wrist 100. The processor 182 may be connected with thecircuit 140 and/or processor 144, or features thereof, of the prostheticwrist 100. The processor 182 is also connected with one or more EMGsensors 186 via respective wires 188. There are five EMG sensors 186.There may be fewer or more EMG sensors 186. The EMG sensors 186 may bein wireless communication with the processor 182. The EMG sensors 186may be a variety of different types of EMG sensors, including surfaceelectrodes, intramuscular electrodes, other types, or combinationsthereof. The EMG sensors 186 are in electrical communication with anatural limb or portion thereof of a user of the prosthetic system 10.Muscular movements, for example contractions, are detected by the EMGsensors 186. Data associated with the muscle movements are communicatedvia the processor 180 to the prosthetic wrist 100 and/or to theprosthetic hand 200. Such data is used to enter a gesture control mode,as described herein. The EMG system 180 may also include an IMU. Forexample, the processor 182 may include or be in communication with anIMU of the lower arm prosthetic 300. The IMU of the lower arm prosthetic300 may provide orientation data about the lower arm prosthetic 300. TheIMU of the lower arm prosthetic 300 may have the same or similarfeatures and/or functionalities as the other IMUs described herein, forexample the IMU 230.

FIG. 7 is a perspective view of an embodiment of a prosthetic arm 301attached to the prosthetic system 10. In some embodiments, theprosthetic system 10 may be used with complete prosthetic arms, not justlower prosthetic arm segments as with the lower arm prosthetic 300. Aproximal end of the prosthetic arm 301 attaches, directly or indirectly,to an upper arm or shoulder of a user. The opposite, distal end of theprosthetic arm 301 is attached to the prosthetic wrist 100 which isattached to the prosthetic hand 200. The prosthetic arm 301 includes anentire arm, i.e. upper and lower arm segments. In some embodiments, theprosthetic arm 301 may include the lower arm prosthetic 300 as well asan upper arm prosthetic connected thereto. Further, the prosthetic arm301 may include a rotatable joint, for example an elbow, incorporatingan IMU 310. The IMU 310 may have the same or similar features and/orfunctionalities as the IMU 230 of the prosthetic hand 200. The IMU 310may detect orientation of the prosthetic arm 301, for example rotationalorientation at the elbow. Such orientation data from the IMU 310 may becommunicated to the prosthetic wrist 100 and/or prosthetic hand 200 forcontrolled movement of the prosthetic wrist 100 and/or prosthetic hand200 in conjunction with, e.g. synchronized with, controlled movement ofthe prosthetic arm 301. The IMU 310 may be used in addition to the IMU230 of the prosthetic hand 200. In some embodiments, the IMU 230 may beused for both wrist rotation and movement of the prosthetic arm 301after a grip has been selected, as described herein. Thus, in someembodiments, a single IMU may perform multiple functions for variousprosthetic segments of the system.

FIG. 8 is a perspective view of an embodiment of a prosthetic arm andshoulder system 400 incorporating the prosthetic system 10. Theprosthetic arm and shoulder system 400 attaches, directly or indirectly,to a side of a user. The prosthetic arm and shoulder system 400 isattached to the prosthetic wrist 100 which is attached to the prosthetichand 200. The prosthetic arm and shoulder system 400 includes an entirearm and shoulder, i.e. upper and lower arm segments and the shoulder. Insome embodiments, the prosthetic arm and shoulder system 400 may includethe lower arm prosthetic 300 as well as an upper arm prosthetic andshoulder prosthetic. Further, the prosthetic arm and shoulder system 400may include one or more rotatable joints. The prosthetic arm andshoulder system 400 may include a rotatable elbow joint incorporatingthe IMU 310. The prosthetic arm and shoulder system 400 may also includea rotatable shoulder joint incorporating an IMU 410. The IMU 410 mayhave the same or similar features and/or functionalities as the IMU 310described herein. The IMU 410 may detect orientation of the prostheticarm and shoulder system 400, for example rotational orientation at theshoulder. Orientation data from the IMU 310 and the IMU 410 may becommunicated to the prosthetic wrist 100 and/or prosthetic hand 200 forcontrolled movement of the prosthetic wrist 100 and/or prosthetic hand200 in conjunction with, e.g. synchronized with, controlled movement ofthe prosthetic arm and shoulder system 400. The IMU 310 and IMU 410 maybe used in addition to the IMU 230 of the prosthetic hand 200. In someembodiments, the IMU 230 may be used for both wrist rotation andmovement of the prosthetic arm 401 after a grip has been selected, asdescribed herein. Thus, in some embodiments, a single IMU may performmultiple functions for various prosthetic segments of the system.

FIG. 9 is a flowchart showing an embodiment of a method 500 foroperating the prosthetic wrist 100. The method 500 may be performed bythe prosthetic system 10 that includes the prosthetic wrist 100 andprosthetic hand 200. The method 500 may be performed by other prostheticsystems that use an IMU sensor to detect an orientation of a prostheticto determine wrist rotation. The method 500 may be performed by theprosthetic wrist 100 and in combination with an IMU associated with theprosthetic hand 200, the prosthetic lower arm 300, the prosthetic arm301, or the prosthetic arm and shoulder system 400. Therefore, themethod 500 may be performed by the prosthetic wrist 100

The method 500 begins with step 501 wherein IMU data associated with theorientation of a prosthetic is received. The IMU data received in step501 may be raw IMU measurements, or calculated results based thereon,such as Euler angles. In step 501, the IMU data is received from the IMU230 and is associated with the orientation of the prosthetic hand 200.In some embodiments, in step 501 the IMU data is received from the IMU310 and is associated with the orientation of the prosthetic arm 301. Insome embodiments, in step 501 the IMU data is received from the IMUs 310and/or 410 and is associated with the orientation of the prosthetic armsystem 400. In step 501, the IMU data is received by the prostheticwrist 100, for example by the processor 144, the circuit 140, orcommunications modules thereof. The IMU data in step 501 may be receivedby wire, for example via the coaxial assembly 160. The IMU data in step501 may be received wirelessly, for example via BLUETOOTH®, WiFi, orother suitable connections.

The method 500 then moves to step 502 wherein a desired hand grip isidentified. The desired hand grip in step 502 may be identified based onone or more gestures performed by the user. For example, in step 502 auser may perform a translation of the prosthetic hand 200, the IMU 230may detect the movement, and the processor 144 or 233 may determine thatthe translation satisfies a movement threshold and identify the desiredgrip based on the specific movement detected. Instead of or in additionto a translation, in some embodiments of step 502 the user may perform anon-linear movement, such as a rotation of the prosthetic hand 200, asweeping movement of the prosthetic hand 200 along a non-linear path,etc. Further details of entering a gesture control mode and detecting agesture movement is described herein, for example with respect to themethod 530 of FIG. 9E and the method 540 of FIG. 9F.

In some embodiments, the desired hand grip is identified in step 502based on receiving a selection of a hand grip from a remote device, suchas a mobile phone or wearable. For example, in step 502 the prosthetichand 200 may communicate the particular gesture to the remote devicewhich may determine the desired grip based thereon and communicate thedesired grip back to the prosthetic hand 200. As further example, instep 502 a user may indicate which grip to perform on the remote device,such as a mobile phone or wearable, and the remote device may thencommunicate the selected desired grip to the prosthetic hand 200. Thus,gesture detection may not be necessary. In some embodiments, the desiredhand grip is identified in step 502 based on receiving a selection of ahand grip from a “grip chip,” as described herein. The prosthetic hand200 may form a particular grip when the prosthetic hand 200 is withinproximity of a corresponding grip chip. The communication to theprosthetic hand 200 from the remote devices, grip chips, etc. may be viaBLUETOOTH®, WiFi, or other suitable connection.

In other embodiments, the desired hand grip may be determined in step502 in a number of other suitable manners, for example by voiceactivation, by gesture pattern recognition, cyclic movement, acyclicmovement, by EMG signal detection, etc. In some embodiments, the desiredhand grip may be determined in step 502 by a combination of these andother means. Some examples of possible approaches to determining thedesired hand grip that may be used step 502 are described in U.S. Pat.No. 8,696,763, titled PROSTHETIC APPARATUS AND CONTROL METHOD and issuedon Apr. 15, 2014, the entire contents of which are incorporated byreference herein for all purposes.

The method 500 then moves to step 503 wherein the wrist rotation isdetermined based on the IMU data and on the desired hand grip. The wristrotation determined in step 503 relates to rotation of the prostheticwrist 100. In step 503, the wrist rotation is determined by theprocessor 144. In some embodiments, in step 503 the wrist rotation maybe determined by the processor 233. The various other electroniccomponents of the prosthetic wrist 100 and/or prosthetic hand 200described herein may determine the wrist rotation in step 503.

The wrist rotation is determined in step 503 by analysis of the currentorientation of the prosthetic hand 200 based on the IMU data,determination of a target orientation of the prosthetic hand 200 basedon the desired hand grip, and comparison of these current and targetorientations.

In step 503, the current orientation of the prosthetic hand 200 based onthe IMU data is analyzed to determine the Euler angles for the currentorientation of the prosthetic hand 200. The IMU data received in step501 is analyzed in step 503 by the processor 144 and/or 233. Otherelectronic components of the prosthetic hand 200 and/or prosthetic wrist100 may perform the analysis. In some embodiments, in step 503processors of other prosthetic components may perform the analysis, suchas processors of the prosthetic lower arm 300, the prosthetic arm 301,or the prosthetic arm and shoulder system 400. In some embodiments, instep 503 processors of other devices may perform the analysis, such asremote devices like a mobile phone, wearable, etc.

In step 503, a particular target orientation for the prosthetic hand 200may be required for a given desired hand grip. In some embodiments, aparticular orientation or range of orientations for the prosthetic hand200 is identified for a given desired hand grip. Thus each hand grip ofa number of possible hand grips may correlate to a particularorientation of the prosthetic hand 200. The target orientations in step503 may be indicated by angular positions for the prosthetic hand 200about one axis, two axes or three axes. Further details of wristrotations based on identified hand grips are described herein, forexample with respect to FIGS. 12A-12F.

In step 503, the difference between the target and current orientationsis analyzed to determine the wrist rotation. The wrist rotationdetermined in step 503 includes a direction of rotation and an amount ofrotation in which to rotate the prosthetic wrist 100. In someembodiments, other parameters of the wrist rotation may be determined instep 503, such as the speed of rotation, the timing of the rotation,etc. Further details of identifying the target orientation, determiningthe current orientation and determining the wrist rotation based on thetarget and current orientations of the prosthetic hand 200 are describedherein, for example with respect to method 548 of FIG. 9G.

The method 500 then moves to step 504 wherein the prosthetic wrist 100is rotated. The rotation of the prosthetic wrist 100 in step 504 isperformed by an actuator such as the motor 130 causing rotation of thecoupling 150 and thus of the prosthetic hand 200 when attached to theprosthetic wrist 100, as described herein. The prosthetic wrist 100 mayrotate in step 504 at a variety of speeds and in a variety ofdirections. In some embodiments, the prosthetic wrist 100 rotatesclockwise or counterclockwise about the longitudinal axis 12. In step504, the prosthetic wrist 100 may be rotated about roll, pitch and/oryaw axes, as described herein.

FIGS. 9B-9G are flowcharts showing embodiments of methods that may beused in combination with the method 500 for rotation of the prostheticwrist 100. FIGS. 9B-9D relate to methods of rotating various prostheticjoints in addition to prosthetic wrists that may be used in combinationwith the method 500.

FIG. 9B is a flowchart showing an embodiment of a method 506 for forminga desired grip with the prosthetic hand 200 in combination with rotationof the prosthetic wrist 100. The method 506 begins with step 508 whereinthe wrist is rotated. Step 508 may perform the steps of the method 500.

The method 506 then moves to step 510 wherein the desired grip is formedwith the prosthetic hand 200. The desired grip may be formed in step 510by moving the prosthetic finger digits 240 and prosthetic thumb digit280 of the prosthetic hand 200. For example, in step 510 the motors 254may cause respective prosthetic finger digits 240 to actuate and/or themotor 291 may cause the prosthetic thumb digit 280 to actuate, asdescribed herein. Only some of the prosthetic finger digits 240 mayactuate in step 510. Other examples of possible approaches to performingthe desired hand grip that may be used step 510 are described in U.S.Pat. No. 8,696,763, titled PROSTHETIC APPARATUS AND CONTROL METHOD andissued on Apr. 15, 2014, the entire contents of which are incorporatedby reference herein for all purposes.

Step 510 is performed as step 508 is performed. The prosthetic wrist 100is thus rotated at the same time that the desired grip is formed withthe prosthetic hand 200. Steps 510 and 508 are thus performed“simultaneously.” “Simultaneously” as used herein includes its ordinaryand usual meaning and includes, for example, at least part of one stepis performed at the same time as at least part of another step. Forexample, in some embodiments, steps 510 and 508 begin at the same timeand end at the same time. As further example, in some embodiments, steps510 and 508 begin at the same time and end at different times. Asfurther example, in some embodiments, steps 510 and 508 begin atdifferent times and end at the same time. The steps 510 and 508 may notbe performed simultaneously. For example, in some embodiments, step 508is performed and then step 510 is performed, or vice versa. For example,the prosthetic wrist 200 may rotate after the prosthetic hand 100 formsthe desired grip, or vice versa.

FIG. 9C is a flowchart showing an embodiment of a method 512 for forminga desired grip with the prosthetic hand 200 in combination with rotationof the prosthetic wrist 100 and rotation of a prosthetic elbow. Themethod 512 begins with step 514 wherein the wrist is rotated. Step 514may perform the steps of the method 500, described herein. The method512 then moves to step 516 wherein the desired grip is formed with theprosthetic hand 200. Step 516 is the same as step 510 of the method 506,described herein. The method then moves to step 518 wherein the elbow isrotated. The prosthetic elbow rotated in step 518 may be part of theprosthetic lower arm 301. In step 518 the prosthetic lower arm 301 maythus be rotated, as described herein. The prosthetic lower arm 301 maybe rotated based on IMU data received by one or more IMU sensors, suchas the IMU 230 and/or the IMU 310. Steps 514, 516 and 518 are performedsimultaneously. In some embodiments, only some or none of the steps 514,516 and 518 are performed simultaneously. For example, two of the steps514, 516 and 518 may be performed simultaneously while the third step isperformed before or after the other two steps.

FIG. 9D is a flowchart showing an embodiment of a method 520 for forminga desired grip with the prosthetic hand 200 in combination with rotationof the prosthetic wrist 100 and rotation of a prosthetic elbow andshoulder. The method 520 begins with step 522 wherein the wrist isrotated. Step 522 may perform the steps of the method 500, describedherein. The method 520 then moves to step 524 wherein the desired gripis formed with the prosthetic hand 200. Step 524 is the same as step 510of the method 506, described herein. The method then moves to step 526wherein the elbow is rotated. Step 526 may be the same as step 518 ofthe method 512, described herein. In some embodiments, step 526 issimilar to step 518 of the method 512 but includes rotation of the elbowjoint of the prosthetic arm and shoulder system 400. The method thenmoves to step 528 wherein the prosthetic shoulder is rotated. Theprosthetic shoulder rotated in step 528 may be part of the prostheticarm and shoulder system 400. In step 528 the prosthetic arm and shouldersystem 400 may thus be rotated, as described herein. The prosthetic armand shoulder system 400 may be rotated based on IMU data received by oneor more IMU sensors, such as the IMU 230, the IMU 310 and/or the IMU410. Steps 522, 524, 526 and 528 are performed simultaneously. In someembodiments, only some or none of the steps 522, 524, 526 and 528 areperformed simultaneously. For example, two of the steps 522, 524, 526and 528 may be performed simultaneously while the other two steps areperformed before or after the first two simultaneous steps. As furtherexample, three of the steps 522, 524, 526 and 528 may be performedsimultaneously while the remaining step is performed before or after thefirst three simultaneous steps.

FIG. 9E is a flowchart of an embodiment of a method 530 of rotating theprosthetic wrist 100 and forming a desired grip with the prosthetic hand200 using gesture control. The method 530 begins with 532 wherein agesture control mode is entered. The gesture control mode may be enteredin step 532 as described with respect to the method 540 in FIG. 9F. Thegesture control mode may be entered in step 532 as described withrespect to step 502 of the method 500 in FIG. 9A. Examples of possibleapproaches to entering a gesture control mode that may be used step 532are described in U.S. Pat. No. 8,696,763, titled PROSTHETIC APPARATUSAND CONTROL METHOD and issued on Apr. 15, 2014,the entire contents ofwhich are incorporated by reference herein for all purposes. The step502 may incorporate some or all of the steps of the method 540,described with respect to FIG. 9F.

The method 530 then moves to step 534 wherein a gesture movement isdetected and analyzed. The gesture movement in step 534 may be detectedas described with respect to step 502 of the method 500 in FIG. 9A. Instep 534, the IMU 230 of the prosthetic hand 100 detects user movements,for example translations, rotations, vibrations, etc., of the prosthetichand 100. In some embodiments, in step 534 the prosthetic hand 100 maybe moved in the north, south, east, west, up or down directions, orcombinations thereof, as described with respect to and shown in FIG.12A. Examples of possible approaches to detecting a gesture movementthat may be used step 534 are described in U.S. Pat. No. 8,696,763,titled PROSTHETIC APPARATUS AND CONTROL METHOD and issued on Apr. 15,2014, the entire contents of which are incorporated by reference hereinfor all purposes.

The gesture movement may be analyzed in step 534 to determine if agesture movement threshold was satisfied. In some embodiments of step534, the gesture movement may be analyzed over a set period of time, forexample every 1,000 milliseconds (ms). If the gesture movement thresholdis satisfied within the period of time, the grip is affected. Otherwise,the process times out and returns to waiting for a trigger or indicationto enter gesture control mode again.

In some embodiments of step 544, an acceleration threshold may beimplemented. For example, the threshold may be an acceleration meetingor exceeding a particular amount in a particular direction, for instancealong a particular axis. In some embodiments, two axes are used, suchthat an acceleration satisfying the acceleration threshold in eitherdirection along either of the two axes satisfies the threshold. The twoaxes may be the North-South axis and East-West axis indicated in FIG.12A. If accelerations satisfying the acceleration threshold are detectedalong both axes, then the larger acceleration may be used to determinethe gesture movement. The threshold acceleration amount may be within arange of about 1.05g to 1.3g. The threshold acceleration amount may bebetween a range of about 1.1g to 1.2g. The threshold acceleration amountmay be about 1.1g. The threshold acceleration amount may be 1.1g.

The method 530 then moves to step 536 wherein one or more rotations areperformed. In step 536, the prosthetic wrist 100 rotates. In someembodiments, in step 536 the prosthetic arm 301 and/or prosthetic armand shoulder system 400 also rotate. The rotations of these prostheticsin step 536 may be as described herein, for example with respect to thesteps 522, 526 and 528 of the method 520 in FIG. 9D.

The method 530 then moves to step 538 wherein the desired grip is formedwith the prosthetic hand 200. The desired grip may be formed in step 528as described herein, for example, with respect to step 510 of the method506 in FIG. 9B.

FIG. 9F is a flowchart showing an embodiment of a method 540 forentering gesture control mode. The method 540 may be incorporated intothe step 532 of the method 530. The method 540 begins with step 542wherein an EMG signal is received. The EMG signal is generated in step542 by the muscle of a user. For example, in step 542 a user may performa pre-determined muscle movement, such as a co-contraction or hold-openmovement, to generate a corresponding EMG signal. The EMG signal may bereceived in step 542 from the EMG sensors 186 of the EMG system 180. Instep 542, data associated with the detected EMG signal may betransmitted to the processor 182 of the EMG system 180 and/or theprocessor 144 of the prosthetic wrist 100 and/or the processor 233 ofthe prosthetic hand 200. The data associated with the EMG signal isanalyzed in step 542 by one of the various processors and determined tobe associated with entering a gesture control mode.

The method 540 then moves to step 544 wherein the orientation of aprosthetic is determined with one or more IMUs. In step 544, theorientation of the prosthetic hand 200 may be determined by the IMU 230or by another IMU of the prosthetic hand 200. The processor 144 maycommand the IMU 230 to detect the orientation based on receiving the EMGsignal in step 542. In some embodiments, the orientation of theprosthetic arm 301 is detected by the IMU 310, and/or the orientation ofthe prosthetic arm and shoulder system 401 is detected by the IMU 310and/or the IMU 410.

In some embodiments of step 544, the orientation of the prosthetic isdetermined after a settling period. For example a chip, such as theprocessor 233, may settle for a first period of time to determine anynecessary offsets. In some embodiments, the settling period may be fromabout 10 to 100 milliseconds (ms). In some embodiments, the settlingperiod time may be about 40 ms. In some embodiments, the settling periodtime may be 40 ms. After the settling period, the Euler angles may becalculated over a calculation period. In some embodiments, thecalculation period may be from about 10 to 100 ms. In some embodiments,the calculation period may be about 40 ms. In some embodiments, thecalculation period may be 40 ms. An average of the Euler anglescalculated during the calculation period may be determined as theorientation.

The determined orientation may be analyzed in step 544 to determine ifan orientation threshold was satisfied. The orientation threshold may beindicative of various desirable prosthetic hand 200 positions forentering gesture control mode, such as palm up, palm down, thumb up, orparallel to the ground.

The method 540 then moves to step 546 wherein entry to gesture controlmode is indicated. Indication may be provided in step 546 by movement ofone or more of the prosthetic finger digits 240 and/or the prostheticthumb digit 280. In some embodiments, a particular prosthetic fingerdigit 240, for example the forefinger, will twitch. A twitch may be aslight rotation in a first direction and then a slight rotation in theopposite direction.

The methods 530 and 540 may be combined to combine gesture control modewith rotation of the prosthetic wrist 100 and formation of the desiredgrip of the prosthetic hand 200. In some embodiments, pitch and rollaxes may be used with particular parameters. Example parameters for suchembodiments are provided in Tables 1, 2 and 3 below.

TABLE 1 Example gesture control parameters for an extra small leftprosthetic hand 200. Hand size XS Left check pitch −0.4 . . . 0.4 otherpointing = horizontal down or up check roll −1 . . . +1 <−2.1 or ><−1.25 >=−1.25 reject +2.1 orientation = palm up palm down pinky upthumb up angle = 90 + pitch pitch − 90 reject 90 − roll

TABLE 2 Example gesture control parameters for an extra small rightprosthetic hand 200. Hand size XS Right check pitch −0.4 . . . 0.4 otherpointing = horizontal down or up check roll −1 . . . +1 <−2.1 or > >1.25<=1.25 reject +2.1 orientation = palm up palm down pinky up thumb upangle = 90 + pitch pitch − 90 reject 90 − roll

TABLE 3 Example gesture control parameters for small, medium and largesizes of left and right prosthetic hands 200. Hand size S/M/L Left/Rightcheck pitch −1.1 . . . 1.1 >1.25 other thumb not thumb up pinky up thumbpointing = up check roll −0.4 . . . +0.4 <−2.8 or > other reject 90 −+2.8 pitch orientation = palm up palm down hand pointing down or upangle = 90 + roll 90 − roll reject

FIG. 9G is a flowchart showing an embodiment of a method 548 fordetermining the required rotation of the prosthetic wrist 100. Themethod 548 may be used in step 503 of the method 500 in FIG. 9A. Themethod 548 begins with step 550 wherein a target orientation for theprosthetic hand 200 is identified. The target orientation may includeorientations about one, two or three axes. The target orientation may bedetermined in step 550 based on the identified desired grip, for exampleas described in step 502 of the method 500. In step 550, the targetorientation may be identified based on a pre-determined relationshipbetween various grips and corresponding wrist orientations. For example,formulas, databases or other means may be used to analyze therelationship. In some embodiments, each grip requires a particularangular orientation of the prosthetic hand 200 about the longitudinalaxis 12. In some embodiments, the target orientation is based on thatparticular angular orientation. In some embodiments, that particularangular orientation is the target orientation. In some embodiments, thatparticular angular orientation may be modified based on the determinedcurrent orientation of the prosthetic hand 200. For example, theprosthetic hand 200 may require multiple rotations, segmented rotations,and the like. Thus, the target orientation may include one or moreangular orientations, such as rotation to a first angle and thenrotation to a second angle.

The method 548 then moves to step 552 wherein the current orientation ofthe prosthetic hand 200 is determined based on the IMU data associatedwith the prosthetic hand 200. The IMU data may be based on detecting theorientation of the prosthetic hand 200 with the IMU 230, as describedherein. The orientation of the prosthetic hand 200 may indicate thecurrent rotational position of the prosthetic wrist 100. For example,the prosthetic wrist 100 may have rotated the hand previously, and thecurrent orientation of the prosthetic hand 200 may be indicative of therotated position of the prosthetic wrist 100. As further example, a usermay have manually rotated the prosthetic hand 200, and thus the currentorientation of the prosthetic hand 200 may be used to determine themanually rotated position of the prosthetic wrist 100. As furtherexample, a user may have just installed the prosthetic hand 200 onto theprosthetic wrist 100, and thus the current orientation of the prosthetichand 200 may be used to determine the installed position of theprosthetic wrist 100

The method 548 then moves to step 554 wherein the required wristrotation direction and angle are determined. The angle is determined instep 554 by comparing the current and target orientations of theprosthetic wrist 100. For example, it may be determined that achievingthe target orientation requires a rotation of thirty degrees in theclockwise direction from the current orientation.

FIGS. 10A-10D are embodiments of remote devices that may be used withthe hand and wrist system 10. FIGS. 10A-10C show example embodiments ofa mobile device 600 with various screen displays. The mobile device 600may be used, for example via the touch screen, with grip indicatorsoftware, such as apps, to indicate desired grips, which may be based onparticular gesture movements. The remote device 600 may include “quickgrips” icons that a user can select, for example by touching on thescreen, and then via the software the prosthetic hand 200 will move intothe programmed grip and the prosthetic wrist 100 will rotate theprosthetic hand 200 to the required position for that specific grip. Theremote device 600 may or may not be used with gesture control. Theselection of a grip with the remote device 600 may be used inconjunction with the various other prosthetic movements, such as wrist,elbow and/or shoulder rotation. FIG. 10D shows an example embodiment ofa wearable device 700 with a screen display. The wearable device 700 maybe used, for example via the touch screen, voice activation, etc. toindicate desired grips based on particular gesture movements. Thedevices 600, 700 may be communicated with via touch, voice control, fromother devices, and/or by other suitable means. In some embodiments, bothdevices 600, 700 may be used in combination with the prosthetic wrist100 and/or prosthetic hand 100.

FIG. 11 is an embodiment of a control system 800 that may be used tocontrol the hand and wrist system 10. The control system 800 includes aprosthetic wrist actuator 810 in communicating connection with aprosthetic wrist controller 820. The prosthetic wrist actuator 810 mayinclude the various prosthetic wrist actuators described herein, forexample the motor 130 and/or other components of the prosthetic wrist100. The prosthetic wrist controller 820 may include the variousprosthetic wrist control devices described herein, for example theprocessor 144 or circuit 140 of the prosthetic wrist 100. The prostheticwrist controller 820 may also be separate from the prosthetic wrist 100,for example it may be part of the prosthetic hand 200, the prostheticlower arm 300, the prosthetic arm 301, the prosthetic arm and shouldersystem 400, the remote devices 600 and/or 700. In some embodiments, theprosthetic wrist controller 820 is distributed among these or otherdevices. The prosthetic wrist controller 820 may include a number ofsuitable types of controllers and control techniques, including forexample open loop, closed loop, feedback, partial-integrative-derivative(PID), programmable logic controller (PLC), microcontroller, on-off,linear, proportional, non-linear, fuzzy logic, other types, orcombinations thereof.

The prosthetic wrist controller 820 receives data from one or moresensors and commands the prosthetic wrist actuator 810 based on thereceived data. The prosthetic wrist controller 820 is in communicatingconnection with a prosthetic hand IMU 830, a prosthetic elbow IMU 840, aprosthetic shoulder IMU 850, and a desired grip indicator 860. In someembodiment, the prosthetic wrist controller 820 is in communicatingconnection with only one or some of these components. In someembodiments, the prosthetic wrist controller 820 is in communicatingconnection with other components. The prosthetic hand IMU 830,prosthetic elbow IMU 840, prosthetic shoulder IMU 850, and desired gripindicator 860 communicate data, information, signals, etc. to theprosthetic wrist controller 820 for controlling the prosthetic wristactuator 810.

The prosthetic hand IMU 830, prosthetic elbow IMU 840, and prostheticshoulder IMU 850 may be any of the various types of IMUs describedherein, including for example a nine-axis IMU. The IMUs 830, 840 and 850may be the same or different type of IMUs. In some embodiments, the IMUs830, 840 and 850 may be the same IMU. The prosthetic hand IMU 830 may bethe IMU 230 of the prosthetic hand 200. In addition or alternatively, insome embodiments the prosthetic hand IMU 830 may include other IMUs ofthe prosthetic hand 200. The prosthetic elbow IMU 840 may be the IMU 310of the prosthetic arm 301. In addition or alternatively, in someembodiments the prosthetic elbow IMU 840 may include other IMUs of theprosthetic arm 301. The prosthetic shoulder IMU 850 may be the IMU 410of the prosthetic arm 400. In addition or alternatively, in someembodiments the prosthetic elbow IMU 850 may include other IMUs of theprosthetic arm 400.

The control system 800 may be used to perform the various methodsdescribed herein. In some embodiments, the control system 800 may beused to perform the method 500, the method 506, the method 512, themethod 520, the method 530, the method 540 and/or the method 548. Theprosthetic wrist controller 820 may receive data from the IMUs 830, 840and 850 and command the prosthetic wrist actuator 810 to perform thevarious methods or steps thereof. The control system 800 may alsoinclude the prosthetic hand 200 and components thereof, for example toform a desired grip. The prosthetic wrist actuator 810 may be consideredto include, for example, the various prosthetic hand motors such as oneor more of the prosthetic finger motors 254, the prosthetic thumb motor291, the motor assembly 220 and thumb rotator 222, etc. The controlsystem 800 may also include the prosthetic lower arm 300, the prostheticarm 301, and/or the prosthetic arm and shoulder system 401, andcomponents thereof, for example to rotate an arm or receive datatherefrom. The prosthetic wrist actuator 810 may be considered toinclude, for example, various prosthetic arm, elbow, and/or shouldermotors.

The desired grip indicator 860 communicates a desired grip to theprosthetic wrist controller 820. The desired grip indicator 860 may bean EMG system, for example the EMG system 180, and communicate EMGsignals or associated data to the prosthetic wrist controller 820. Suchsignals may be analyzed by the prosthetic wrist controller 820, forexample to determine if a gesture control mode should be entered. Thedesired grip indicator 860 may be or include an IMU that measures amovement of the user, such as a gesture performed by the user toindicate a particular grip, as described herein. The desired gripindicator 860 may be or use the IMUs 830, 840 and/or 850. The desiredgrip indicator 860 may be a remote device that provides the desiredgrip, for example the remote devices 600 and/or 700.

FIGS. 12A-12F are sequential perspective views of the prosthetic wristand arm system 10 showing simultaneous grip formation of the prosthetichand 200 and rotation with the prosthetic wrist 100. The geometricreference North-South-East-West system is indicated, with perpendicular“up” and “down” directions. The North-South-East-West are in a planegenerally aligned with the longitudinal axis 12 (see FIG. 12B) andparallel to the ground. Other orientations of the North-South-East-Westsystem may be implemented. The system 10 may be moved, for exampletranslated, in one of the indicated directions to register anacceleration that satisfies an acceleration threshold, as describedherein. The prosthetic system 10 may then perform the grip formation andwrist rotation, as described herein.

The grip formation and wrist rotation may begin such that the system 10has the configuration as shown in FIG. 12A, with the palm of theprosthetic hand 200 up and generally parallel to theNorth-South-East-West plane, and the prosthetic finger digits 240A,240B, 240C and 240D and prosthetic thumb digit 280 extended as shown.

The grip formation and wrist rotation may continue such that theprosthetic system 10 has the configuration as shown in FIG. 12B at alater point in time compared to FIG. 12A. As shown in FIG. 12B, theprosthetic digits 240A, 240B, 240C, 240D, 280 are bent slightly towardthe palm fairing 226 in the direction 13 as indicated, and theprosthetic hand 200 has rotated slightly about the longitudinal axis 12in the direction 14 as indicated, as compared to FIG. 12A. Theprosthetic digits 240B, 240C, 240D are bent slightly farther than theprosthetic digit 240A.

The grip formation and wrist rotation may continue such that theprosthetic system 10 has the configuration as shown in FIG. 12C at alater point in time compared to FIG. 12B. As shown in FIG. 12C, theprosthetic digits 240B, 240C, 240D, 280 are bent farther toward the palmfairing 226, and the prosthetic hand 200 has rotated farther about thelongitudinal axis 12, as compared to FIG. 12B. The prosthetic digit 240Amay have the same curvature as in the FIG. 12B. The prosthetic digits240B, 240C, 240D are further bent more than the prosthetic digit 240A.

The grip formation and wrist rotation may continue such that theprosthetic system 10 has the configuration as shown in FIG. 12D at alater point in time compared to FIG. 12C. As shown in FIG. 12D, theprosthetic digits 240B, 240C, 240D, 280 are bent farther toward the palmfairing 226, and the prosthetic hand 200 has rotated farther about thelongitudinal axis 12, as compared to FIG. 12C. The prosthetic digit 240Amay have the same curvature as in the FIG. 12C. The prosthetic digits240B, 240C, 240D are further bent more than the prosthetic digit 240D.

The grip formation and wrist rotation may continue such that theprosthetic system 10 has the configuration as shown in FIG. 12E at alater point in time compared to FIG. 12D. As shown in FIG. 12E, theprosthetic digits 240B, 240C, 240D, 280 are bent farther toward the palmfairing 226, and the prosthetic hand 200 has rotated farther about thelongitudinal axis 12, as compared to FIG. 12D. The prosthetic digit 240Amay have the same curvature as in the FIG. 12D. The prosthetic digits240B, 240C, 240D are further bent more than the prosthetic digit 240A.The dorsal fairing 224 is approximately perpendicular to theNorth-South-East-West plane.

Finally, the grip formation and wrist rotation may end such that theprosthetic system 10 has the configuration as shown in FIG. 12F at alater point in time compared to FIG. 12E. As shown in FIG. 12F, theprosthetic digits 240B, 240C, 240D, 280 are curled completely or mostlytoward the palm fairing 226, and the prosthetic hand 200 has rotatedfarther about the longitudinal axis 12, as compared to FIG. 12E. Theprosthetic digit 240A may have the same curvature as in the FIG. 12E.The prosthetic digits 240B, 240C, 240D are further bent more than theprosthetic digit 240A. The dorsal fairing 224 is approximately parallelto the North-South-East-West plane. This is merely one example and avariety of other combinations of wrist rotations and grip formations maybe performed with the system 10.

FIGS. 13A-14C are various views of the prosthetic wrist 100 having asecurement system 107 with a coupling, shown as the expanding ring 112,in various configurations. In particular, FIGS. 13A-13C depict theexpanding ring 112 in an unexpanded configuration, FIGS. 14A-14C depictthe expanding ring 112 in an expanded configuration. FIG. 13A is apartial cross-section view of the prosthetic wrist 100 showing theexpanding ring 112 in an unexpanded configuration, and FIGS. 13B-13C arepartial cross-section views of the prosthetic arm 300 with the wrist 100therein showing the prosthetic wrist 100 with the expanding ring 112 inan unexpanded configuration.

FIG. 13A is a detail view of the cross-section view of the distal end103 of the prosthetic wrist 100 and securement system 107 having theexpanding ring 112 shown in FIG. 2E. In some embodiments, the securementsystem 107 or portions thereof may be located farther proximally alongthe prosthetic wrist 100.

As shown in FIG. 13A, the securement system 107 includes an actuator105, shown as a threaded shaft. The actuator 105 has an elongated,cylindrical structural body. The actuator 105 includes outer threads105A extending partially along an outer surface of the body. Theactuator 105 extends through an opening 104A of the bearing race 104.The opening 104A has complementary internal threads that engage theouter threads 105A of the actuator 105. With the actuator 105 engagedwith the bearing race 104, the actuator is axially stationary. Rotationof the actuator 105 in a first direction will cause the actuator 105 toadvance axially in a proximal direction, and rotation of the actuator105 in a second opposite direction will cause the actuator 105 toadvance axially in a distal direction. Advancing the actuator 105proximally will cause a proximal end 105B to contact the pressure ring110. Further proximal advance of the actuator 105 will cause thepressure ring 110 to advance proximally as well. In some embodiments,the actuator 105 is a screw or bolt with external threads and having anengagement feature, such as a recess, on the distal side thereof forengagement with a corresponding tool for rotating the actuator 105, suchas a screw driver.

There may be more than one actuator 105. FIG. 13A depicts a detail ofone portion of the securement system 107. It is understood that othersimilar portions of the securement system 107 may be included. There maybe two, three, four, five, six, seven, eight or more such portions. Asdescribed herein, there are three such portions, as more clearly shownfor example in FIG. 13C, having three actuators 105. The actuators 105are shown located at or near outer edges of the body 101 of theprosthetic wrist 101. The actuators 105 are located at similar or thesame radial locations relative to the axis 12. In some embodiments, theactuators 105 may be at other radial locations and/or different radiallocations from each other. The actuators 105 are located at similar orthe same angular locations about the axis 12 relative to each other. Insome embodiments the actuators 105 may be in different angular locationsabout the axis 12 with respect to each other.

In some embodiments, the actuator 105 may be other shapes andconfigurations and/or have different engagement features. For example,the actuator 105 may have a non-cylindrical body, there may be nothreads 105A, there may be threads 105A extending along an entire lengththereof, the actuator 105A may not be elongated axially, there may beone or more intermediate structures in between the actuator 105 and thepressure ring 110, other suitable modifications, or combinationsthereof. In some embodiments, other types of engagements besides or inaddition to threads may be used, such as push pin, friction fit,notches, springs, rack and pinion, other suitable engagements, orcombinations thereof. The opening 104A in the bearing race 104 may beaccordingly modified to accommodate these other types of engagements.

The securement system 107 includes the pressure ring 110. The pressurering 110 may include any of the features of the pressure ring 110described herein, for example with respect to FIGS. 2A-2E. As shown inFIG. 13A, the pressure ring 110 includes a distal end 110A, a proximalend 110, an outer surface 110C, and an inner surface 110D. Thesefeatures may extend circumferentially along the pressure ring 110 aroundthe body 101 of the prosthetic wrist 100. As shown the pressure ring 110extends circumferentially about the distal body 122. The distal end 110Aincludes a bearing surface that is contacted by the proximal end 105B ofthe actuator 105. The inner surface 110D of the pressure ring 110extends about and faces the body 101. As shown the inner surface 110Dfaces the distal body 122. The proximal end 110B faces and may contactthe expanding ring 112. The proximal end 110B is ramped at an angle withrespect to the outer and inner surfaces 110C, 110D. The ramped proximalend 110B extends from the outer surface 110C inwardly in the proximaldirection to the inner surface 110D. In some embodiments the proximalend 110B may be flat, for example at a ninety degree angle with respectto the outer and inner surfaces 110C, 110D. The proximal end 110B mayextend from the outer surface 110C radially inwardly to the innersurface 110D. The outer surface 110C faces outward away from the body101. The outer and inner surfaces 110C, 110D may be longer than thesurfaces on the distal and proximal ends 110A, 110B, or vice versa.

The pressure ring 110 may be contacting the body 101 of the prostheticwrist 100 in one or more places. The pressure ring 110 is showncontacting an outer surface of the distal body 122. In addition oralternatively, the pressure ring 110 may contact other portions of thebody 101. The inner surface 110D of the pressure ring 110 is contactingan outer surface of a distal portion 122A of the distal body 122. Insome embodiments, the pressure ring 110 may be offset from and notcontacting the body 101 in one or more places. The pressure ring 110 maybe rotationally stationary about the axis 12. The pressure ring 110 maybe compressed onto the body 101 such that a friction force existsbetween the pressure ring 110 and parts of the body 101, such as thedistal body 122. In some embodiments, the pressure ring 110 may not berotationally stationary about the axis 12.

The pressure ring 110 may transmit forces applied by the actuator 105 tothe expanding ring 112. Axial movement of the actuator 105 will causethe pressure ring 110 to move axially. The proximal movement of theactuator 105 will cause the proximal end 105B to contact and bearagainst the distal end 110A of the pressure ring 110, moving thepressure ring 110 proximally. The pressure ring 110 may slide along thebody 101, such as along the distal body 122. As shown the pressure ring110 slides along the distal portion 122A of the distal body. In someembodiments, the pressure ring 110 may move in a different manner and/oralong different parts of the body 101. For example, the pressure ring110 may slide, rotate, jerk, vibrate, move in other suitable manners, orcombinations thereof. The pressure ring 110 may make these and othermovements along one or more other parts of the prosthetic wrist 100,such as other parts of the body 101. The inner surface 110D of thepressure ring 110 is shown as smooth. In some embodiments, the innersurface 110D may be rough, include protrusions, have other features, orcombinations thereof. In some embodiments, the securement system 107 maynot include the pressure ring 110. For example the actuator 105 maycontact the expanding ring 112 directly. The pressure ring 110 may moveaxially toward a recess 122D of the distal body 122 to contact theexpanding ring 112.

The securement system 107 includes the expanding ring 112. The expandingring 112 may include any of the features of the expanding ring 112described herein, for example with respect to FIGS. 2A-2E. The expandingring 112 may include any of the features of the pressure ring 110described herein.

As shown in FIG. 13A, the expanding ring 112 includes a distal end 112A,a proximal end 112B, an outer surface 112C and an inner surface 112D.These features may extend circumferentially along the expanding ring 112around the body 101 of the prosthetic wrist 100. As shown the expandingring 112 extends circumferentially about the distal body 122. Theexpanding ring 112 may have a first end 112F and a second opposing end112G forming a gap 112E therebetween, as shown in FIGS. 13B and 13C.Thus the expanding ring 112 may be an incomplete ring with separatedends 112F, 112G. The expanding ring 112 may form the gap 112E having afirst width G1 (shown in FIGS. 13B and 13C) in the unexpandedconfiguration that is smaller than a second width G2 of the gap 112E inthe expanded configuration (shown in FIGS. 14B and 14C).

In some embodiments, the expanding ring 112 may include one or moreseparated, circumferential segments each defining gaps 112Etherebetween. For example, there may be a first circumferential segmentof the expanding ring 112 that is separated from a secondcircumferential segment of the expanding ring 112, with a first gap 112Elocated between first opposing ends of the segments and a second gap112E located between second opposing ends of the segments. There may betwo three, four, five, six, seven, eight, or more such segments with acorresponding number of gaps 112E. The various segments may berotationally stabilized to maintain a desired separation between thesegments. Each segment may have the first and second ends 112F, 112Gforming the respective gaps 112G on either side of the segment.

The expanding ring 112 may extend substantially within the recess 122Dformed in the distal body 122. The inner surface 112D of the expandingring 112 extends about and faces the body 101. As shown the innersurface 112D faces the distal body 122, for example the recess 122D. Theouter surface 110C faces outward away from the body 101. The outer andinner surfaces 110C, 110D may be longer than the surfaces on the distaland proximal ends 110A, 110B, or vice versa.

The distal end 112A of the expanding ring 112 includes a bearing surfacein contact with the proximal end 110B of the pressure ring 110. Thedistal end 112A is ramped at an angle with respect to the outer andinner surfaces 112C, 112D. The ramped distal end 112A extends from ornear the outer surface 112C inwardly in the proximal direction to ornear the inner surface 112D. The ramped distal end 112A of the expandingring may complement the contour, e.g. the ramped surface, of theproximal end 110B of the pressure ring 110. In some embodiments thedistal end 112A may be flat, for example at a ninety degree angle withrespect to the outer and inner surfaces 112C, 112D. The distal end 112Amay extend from the outer surface 110C radially inwardly to the innersurface 110D.

The proximal end 112B of the expanding ring 112 is ramped at an anglewith respect to the outer and inner surfaces 112C, 112D. The rampedproximal end 112B extends from or near the outer surface 112C inwardlyin the distal direction to the inner surface 112D. The proximal end 112Bmay complement the contour, e.g. the ramped surface, of a proximalportion 122B of the distal body 122. The proximal end 112B includes abearing surface in contact with the proximal portion 122B of the distalbody 122.

The expanding ring 112 may be contacting the body 101 of the prostheticwrist 100 in one or more places. The expanding ring 112 is showncontacting an outer surface of the distal body 122. In addition oralternatively, the expanding ring 112 may contact other portions of thebody 101. The inner surface 112D of the expanding ring 112 is contactingan outer surface of the recess 122D of the distal body 122. In someembodiments, the expanding ring 112 may be offset from and notcontacting the body 101 in one or more places, for example there may bea gap in between the inner surface 112D and a bottom surface of therecess 122D. The expanding ring 112 may be rotationally stationary aboutthe axis 12. The expanding ring 112 may be compressed onto the body 101such that a friction force exists between the expanding ring 112 andparts of the body 101, such as the distal body 122, and/or with otherparts of the prosthetic wrist 100 such as the pressure ring 110. In someembodiments, the pressure ring 110 may not be rotationally stationaryabout the axis 12.

The expanding ring 112 may receive forces applied by the actuator 105via the pressure ring 110. Axial movement of the actuator 105 will causethe pressure ring 110 to move axially, as described. The proximalmovement of the pressure ring 110 will cause the distal end 110B tocontact and bear against the proximal end 112A of the expanding ring112, moving the expanding ring 112 proximally. The expanding ring 112may slide along the body 101, for example along the distal body 122. Asshown the expanding ring 112 slides along the proximal portion 122B ofthe distal body 122.

In some embodiments, the expanding ring 112 may move in a differentmanner and/or along different parts of the body 101. For example, theexpanding ring 112 may slide, rotate, jerk, vibrate, move in othersuitable manners, or combinations thereof. The expanding ring 112 maymake these and other movements along one or more other parts of theprosthetic wrist 100, such as other parts of the body 101. The innersurface 112D of the expanding ring 112 is shown as smooth. In someembodiments, the inner surface 112D may be rough, include protrusions,have other features, or combinations thereof. In some embodiments, thesecurement system 107 may not include the pressure ring 110. For examplethe actuator 105 may contact the expanding ring 112 directly. In someembodiments, there may be intermediate structures between the actuator105 and the expanding ring 112 in addition to the pressure ring 110.

As shown in FIGS. 13B and 13C, the prosthetic wrist 100 may be securedwith the arm 300, which may be a prosthetic socket. The arm 300 is shownin cross-section for clarity. The prosthetic wrist 100 may be insertedinto the arm 300 with the securement system 107 in the unexpandedconfiguration shown in FIGS. 13A-13C. The expanding ring 112 may extendcircumferentially from the first end 112F to the second opposing end112G. The arm 300 may be an elastic structure that can compress aboutthe prosthetic wrist 100. With the prosthetic wrist 100 located insidethe arm 300, the securement system 107 may be actuated to better securethe prosthetic wrist 100 within the arm 300, for example to prevent ormitigate the risk of the prosthetic wrist 100 from detaching from orsliding out of the distal end of the arm 300. In the unexpandedconfiguration, the outermost width of the expanding ring 112 may havethe same or similar outermost width as other structures of the body 101,such as the pressure ring 110. The expanding ring 112 may extend fartheroutward or less far outward than other structures, such as the pressurering 110, in the unexpanded configuration. Upon expansion, the expandingring 112 may have a larger width and extend farther outward than otherstructures, such as the pressure ring 110, by a distance D2, as furtherdescribed for example with respect to FIGS. 14A-14C.

FIGS. 14A-14C depict the expanding ring 112 in an expandedconfiguration. FIG. 14A is a partial cross-section view of theprosthetic wrist 100, similar to the portion shown in FIG. 13A, showingthe expanding ring 112 in an expanded configuration, and FIGS. 14B-14Care partial cross-section views of the prosthetic arm 300 with theprosthetic wrist 100 secured therein, showing the prosthetic wrist 100with the expanding ring 112 in an expanded configuration.

As shown in FIGS. 14A-14C, the actuator 105 has been actuated and movedproximally. The proximal end 105B of the actuator 105 is bearing againstthe distal end 110A of the pressure ring 110 to cause the pressure ring110 to move proximally, as indicated by the proximal arrow in FIG. 14A.The distal end 105B may contact a portion of the distal body at thedistal end 122A, for example to provide a stop or travel limit for theactuator 105. Thus the pressure ring 110 is in a relatively moreproximal position in FIGS. 14A-14C as compared to FIGS. 13A-13C. Theoutward expansion of the expanding ring 112 may be proportional to theaxial movement of the actuator 105, such that farther axial advance ofthe actuator 105 will cause farther outward expansion of the expansionring 112. In some embodiments, one, some or all of the actuators 105 maybe actuated.

As further shown in FIGS. 14A-14C, the pressure ring 110 is bearingagainst the expanding ring 112. The ramped proximal end 110B of thepressure ring 110 is bearing against the complementary ramped surface ofthe distal end 112A of the expanding ring 112. The pressure ring 110when moved proximally may be partially located on an inner side of theexpanding ring 112. This causes an outward movement of the expandingring 112.

The expanding ring 112 is bearing against the distal body 122. Theramped distal end 112B of the expanding ring 112 is bearing against acomplementary ramped surface 122C of the proximal portion 122B of thedistal body 122. The ramped surface 122C may extend from a first radialinward location in the proximal direction to a second radial outwardlocation that is located farther outward radially compared to the firstradial inward location. The expanding ring 112 may be partially locatedon an upper side of the proximal portion 122B. This further causes anoutward movement of the expanding ring 112. This may also allow for aproximal movement of the expanding ring 112 in the expandedconfiguration.

The engagement of the various ramped surfaces thus causes an outwardmovement of the expanding ring 112. The expanding ring 112 is thuslocated farther from the body 101, for example farther from the distalbody 122, in the expanded configuration shown in FIGS. 14A-14C ascompared to the unexpanded configuration shown in FIGS. 13A-13C. Theexpanding ring 112 may move, partially or entirely, away from the body101. The expanding ring 112 may move in a direction radially outwardaway from the axis 112, as shown by the “radial” direction arrows inFIG. 14B which may be perpendicular to the axis 12. The coupling, suchas the expanding ring 112 or variations thereof as described herein suchas the segmented expanded ring 112, may be used and configured to movefrom a first configuration to a second configuration, where the couplingin the second configuration is at least partially located farther awayfrom the body 101 as compared to the first configuration, to bettersecure the prosthetic wrist 100 with a prosthetic socket, such as thearm 300, of the user when the prosthetic wrist 100 is coupled with theprosthetic socket.

The expanding ring 112 may thus have a larger width in the expandedconfiguration of FIGS. 14A-14C compared to the unexpanded configurationof FIGS. 13A-13C. The width may be a diameter of the expanding ring 112,for example an outer diameter as measured from a first point on theouter surface 112C to a second point on the outer surface 112C locateddirectly across from the first point, such as one hundred eighty degreesfrom the first point. Thus the outer width of the prosthetic wrist 100may increase. The expanding ring 112 in the expanded configuration mayincrease in width by a distance D2, as shown in FIGS. 14A and 14B. Thedistance D2 may be an increase in the radius of the expanding ring 112,such that the diameter increases by twice D2. The distance D2 may bemeasured relative to the location of the outer surface 112C in theexpanded configuration as compared to the unexpanded configuration. Thedistance D2 may be measured from the outer surface 112C in the expandedconfiguration to the outer surface 110C of the pressure ring 110. Thesetwo measurement may be equal, for example where the outer surfaces 112C,110C line up or have a similar width in the unexpanded configuration.The distance D1 may be various amounts, for example 0.1 cm, 0.2 cm, 0.3cm, 0.4 cm, 0.5 cm, 0.6 cm, 0.7 cm, 0.8 cm, 0.9 cm, 1.0 cm, 1.1 cm, 1.2cm, 1.3 cm, 1.4 cm, 1.5 cm, 1.6 cm, 1.7 c, 1.8 cm, 1.9 cm, 2.0 cm, ormore.

Increasing the outer width of the prosthetic wrist 100 will cause theexpanding ring 112, for example the outer surface 112C, to bear againstan inner surface 304 of the arm 300. The arm 300 defines an opening 302extending at least partially therethrough and into which the prostheticwrist 100 is secured. The opening 302 may be defined by the innersurface 304. The expanding ring 112 in the expanded configuration willbear against the inner surface 304. The increased outer force of theexpanding ring 112 against the arm 300 will better secure the prostheticwrist 100 within the arm 300. The expanded expanding ring 112 willincrease the friction force between the prosthetic wrist 100 and the arm300, such that a larger axial distal force on the prosthetic wrist 100is required to dislodge the prosthetic wrist 100 from the arm 300. Thearm 300 may or may not have corresponding features on the inner surfacethat engage with the expanding ring 112. In some embodiments, the arm300 may have an inner lip or flange, indentations, recesses or the likethat engage with the expanding ring 112 in the expanded configuration.

The gap 112E of the expanding ring 112 is larger in the expandedconfiguration. As shown in FIGS. 14B and 14C, the gap 112E now has alarger width G2 as compared to the unexpanded width G1 (shown in FIGS.13B and 13C). The widths G1 and G2 may be measured circumferentially(e.g. an arc length) or linearly (e.g. a chord). The expanded gap 112Eis larger due to the increased circumference and width of the expandingring 112. Thus the expanding ring 112 may also expand in circumference.In some embodiments, there may be multiple segments of the expandingring 112, as described, and thus multiple gaps 112E with correspondingunexpanded widths G1 and expanded widths G2. In such embodiments, for agiven gap 112E each expanded width G2 may be larger than thecorresponding unexpanded width G1.

The engagement of the various ramped surfaces may cause a proximalmovement of the expanding ring 112. The direction of proximal movementis indicated in FIG. 14A by the proximal direction arrow along theactuator 105 and the pressure ring 110.

The pressure ring 110 may move proximally, as described, which may alsomove the expanding ring 112 proximally. The engagement of the proximalend 112B of the expanding ring 112 with the ramped surface 122C of thedistal body 122 may cause or allow the expanding ring 112 to moveproximally from the unexpanded configuration to the expandedconfiguration upon actuation. The expanding ring 112 may move proximallyby various amounts, for example by 0.1 cm, 0.2 cm, 0.3 cm, 0.4 cm, 0.5cm, 0.6 cm, 0.7 cm, 0.8 cm, 0.9 cm, 1.0 cm, 1.1 cm, 1.2 cm, 1.3 cm, 1.4cm, 1.5 cm, 1.6 cm, 1.7 c, 1.8 cm, 1.9 cm, 2.0 cm, or more.

In some embodiments, the prosthetic hand 200 may be detached from theprosthetic wrist 100 by applying a sufficient torque to the prosthetichand 200. Such torque may be about the axis 12. In some embodiments, thequick wrist disconnect (QWD) features may be used, as described. In suchcases, it is desirable to prevent or mitigate the risk of undesirabledetachment of the prosthetic hand 200 from the prosthetic wrist 100 dueto applying too high of a torque. Therefore, a torque limit may beimplemented to limit the torque applied by the prosthetic wrist. Suchtorque limit may be implemented by limiting the current applied to theactuator module 120 of the prosthetic wrist 100.

FIGS. 15A-15C are data plots showing embodiments of relationshipsbetween current and time during rotation of the prosthetic wrist 100that may be used for controlling torque of the prosthetic wrist 100. TheX axis is time, and the Y axis is drawn current. The current supplied tothe actuator module 120 may be proportional to the torque applied by theprosthetic wrist 100.

In FIG. 15A, the plot shows the drawn current over time for initiatingrotation of the prosthetic wrist under a load. Such load may cause acounter torque to be applied to the prosthetic wrist 100 that must beovercome to cause rotation. The load may be due to the weight of theprosthetic hand 200 and/or an object held by the prosthetic hand 200.The required torque may also depend on the particular prosthetic wrist100 embodiment that is used (which may have different friction levels,size requirements, etc.), the direction of rotation of the prostheticwrist 100, the voltage supplied, other variables, or combinationsthereof.

Under a loaded condition, as shown in FIG. 15A, a first current C1 maybe drawn from initiation of the rotation control signal to time T1.There may be a delay built into the control logic, as shown, such thatC1 is zero and the current draw does not increase until T1. The currentthen rises steeply and approximately linearly from T1 to T2. This linearincrease is a first stage of the applied current. The current may risesteeply and linearly from T1 to T2. This first stage ends when rotationof the prosthetic hand 200 starts, for example as indicated by the Halleffect sensors 142.

After rotation has started, the plot shows a second stage of transitionfrom current ascending to current descending. This is where the currentpeaks, shown as current C2 at time T2. The second stage may be at oraround this peak. The peak may be a global maximum. During this periodthe change in current over the change in time, or the first derivativeof the plot, goes from positive to negative. This second stage isshorter on lighter loads and may be longer for heavier loads, forexample up to 100 ms or about 100 ms.

In a third stage, which may be called a steady current wash out stage,the current then decreases to C3 at time T3. The current may reduce in alinear or approximately linear manner in the third stage. The firstderivative of the plot is negative and may be constant or nearlyconstant. This decrease may be more gradual, i.e. less steep but in theopposite direction, than the steep increase in stage one. Thus theabsolute value of the first derivative of the plot in the third stagemay be less than the absolute value of the first derivative of the plotin the first stage. The current drop may become less pronounced as thecurrent approaches the level of current required to sustain constantrotational speed for the given load.

Next, at or around time T3, the current stops or nearly stops decreasingin a fourth stage, which may be called a transition to equilibrium. Thecurrent may stay at or around C3 in a steady state after time T3. Thechange in the current drop over time becomes less, i.e. it becomes lessnegative and approaches zero. C3 may be less than C2 as shown.

Finally, in a fifth stage, the current is at equilibrium or steadystate. The controller drives the actuator module 120 at a constant speedand the actuator current consumption is steady or approximately steady.The first derivative of the plot is zero or approximately zero. Theaverage of the first derivatives of the plot over this time in the fifthstage may be zero.

In FIG. 15B, the plot shows the applied current over time for initiatingrotation of the prosthetic wrist without a load or with a progressiveloading. Under the unloaded condition, a first current C1 may be appliedfrom initiation of applied current at time T1. The current then risessteeply and linearly from T1 to T2. This linear increase may be a firststage of the applied current. This first stage ends when rotationstarts, for example as indicated by the Hall effect sensors 142. Theremay be a local peak at movement start but current will surpass this peakas load increases. As shown, the peak may be at time T2 with currentlevel C2, which may be a second stage. This peak may be a local maximum.With progressive loading, the current may increase gradually in a thirdstage, toward an equilibrium value C3 at time T3. The current mayovershoot C3 in a fourth stage at a global maximum as shown, or it maynot overshoot C3. The current may settle at or around C3 in a fifthstage. C3 may be greater than C2 as shown.

FIG. 15C shows an example first derivative plot for a relationship ofcurrent over time for an example loaded rotation. The first derivativemay be the change in current over a change in time. The first derivativeis positive but decreasing from time Ti to time T2. The first derivativethen crosses the X axis from positive to negative value at time T2. Thefirst derivative then further decreases and reaches a minimum at oraround time T3, after which it increases and approaches zero but isstill negative up to or at about T4. The first derivative then is at ornearly at zero after T4.

The various stages may be identified based on analysis of the firstderivative of the drawn current versus time relationships. The firststage may be from T1 to T2. The second stage may be at or around T2. Thethird stage may be from T2 to T3. The fourth stage may be form T3 to T4.The fifth stage may be after T4. Similar first derivative plots may beproduced and analyzed for unloaded rotation, progressive loadedrotation, and other types of loaded rotations.

These are merely some example relationships between current and timethat may be used. The particular relationship will depend on a varietyof factors, including the particular embodiment of the wrist 100, theamount of voltage supplied, the weight and other characteristics of theparticular embodiment of the prosthetic hand 200, the amount of load,the desired responsiveness of the rotation to a command signal (forexample amount of delay, time to make the full rotation, etc.), thedirection of rotation (clockwise versus counter clockwise), and otherfactors as described herein. In some embodiments, the length of thesteady wash out period (stage 3) may depend on the load and mechanicalefficiency of the wrist rotator. In some embodiments, rotation may beassisted. On assisted starts, stage 3 may be eliminated as the peak maybe near the running current values. In some embodiments, higher loadsand lower voltage may require more current in a proportional manner. Insome embodiments, the difference in maximum running current between aloaded start and unloaded start may not be significant. This means thatonce the motor exits the start-up stage it may behave the same wayregardless of how much power is required to initiate movement. In someembodiments, a loaded starts as compared to an unloaded start mayincrease both the peak and running current in similar proportion. Insome embodiments, the running current at stable load and speed isindependent from the initial current drawn to start movement.

In some embodiments, a delay may be implemented in entering stage 3 inorder to clear stage two. For example, a delay of 100 ms (milliseconds)or about 100 ms may be implemented in enacting the stage three logic toclear stage two. This may result in small rotations if the load was tobe applied milliseconds after starting movement on an unloaded start.For loaded starts, a delay, such as 100 ms delay, may also result insmall rotations if the peak threshold is not breached but the runningcurrent is above the running current limit. In some embodiments, athreshold may be implemented at which the current drop is consideredsufficiently negative to assume the motor is on stage three or four andhas not reached steady state. For example, a value of −3mA/millisecondmay be used as the threshold at which the current drop is consideredsufficiently negative to assume the motor is on stage three or four andhas not reached steady state. In some embodiments, a running currentlimit should only be applied after stage three and four have been clearout (or if they were never present). In some embodiments, the firmwarelogic may apply the current limit at any point except when movement hasnot started (stage one), within a particular time (e.g. 100 ms or about100 ms) after movement start (stage two), and/or when current isdropping at or greater than a threshold rate, e.g. equal or greater than3mA/ms (stage three or four).

In some embodiments of stage 3, the firmware may calculate the deltacurrent/delta time periodically, e.g. every 40 ms. The value may beapproximated by determining the change in the average of the last tenreadings minus the average of the last thirty to forty readings. In someembodiments, due to this loop in the logic the limit may not be enactedat the first instance of the current drop being less than a threshold,e.g. 3A/s, and may be enacted on the next iteration of the cycle (e.g.40ms after). In some embodiments, the Hall Effect sensors may report achange from 21 to 29 from the start of stage three to the rotationstopping, which may equates to about 2 degrees of movement. The totalamount of movement may be about 7 degrees as a result of the intentionaldelay in applying the running current limit until the peak has passed.To reduce this rotation on loaded starts the peak current limit may beapplied.

The control system may recognize and identify whether the prosthetic isunder a loaded, unloaded, or progressive loading rotation. Appropriatetorque limits may therefore be applied. A single torque limit may not befeasible in all scenarios, for example in a loaded condition. Thereforetwo or more torque limits may be required and a logic to transition fromone limit to the other(s). Various methods may be used to determine thetorque limits and to implement them, as further described.

FIG. 16A is a flow chart showing an embodiment of a method 900 forapplying torque limits for control of the prosthetic wrist 100. Themethod 900 begins with step 910 wherein the stage of rotation of theprosthetic wrist is determined. The first, second, third, fourth, orfifth stage may be identified as described herein, for example withrespect to FIGS. 15A-15C. Step 910 may include analyzing the currentversus time relationship to determine whether the rotation is under aloaded, unloaded or progressive loading condition, in order to determinethe stage of rotation.

The method 900 then moves to step 912 wherein a torque limit isimplemented for the determined stage of rotation. An upper or lowertorque limit may be implemented depending on the stage. In someembodiments, a first torque limit may be implemented to restrict theapplied torque to be no greater than an upper torque limit for variousstages, such as stages one and/or two. Such upper torque limit may be1.2 Nm (Newton-meters) or about 1.2 Nm, which may be 1.2 Nm +/−10%. Insome embodiments, the upper torque limit may be 0.6 Nm, 0.7 Nm, 0.8 Nm,0.9 Nm, 1.0 Nm, 1.1 Nm, 1.3 Nm, 1.4 Nm, 1.5Nm, 1.6 Nm, 1.7 Nm, 1.8 Nm,1.9 Nm, or 2.0 Nm. In some embodiments, a second torque limit may beimplemented to restrict the applied torque to be no less than a lowertorque limit for various stages, such as stages three, four and/or five.Such lower torque limit may be 0.8 Nm or about 0.8 Nm, which may be 0.8Nm +/−10%. In some embodiments, the lower torque limit may be 0.2 Nm,0.3 Nm, 0.4 Nm, 0.5 Nm, 0.6 Nm, 0.7 Nm, 0.8 Nm, 0.9 Nm, 1.0 Nm, 1.1 Nm,1.3 Nm or 1.4 Nm.

The current limits corresponding to these torque limits for a givenvoltage may be implemented in the control system, where thecorresponding currents for these torques may be determined fromcalibration or testing of the particular embodiments of the prostheticwrist 100 and hand 200 being used. The currents may range from zero toabout 3,000 Ma, or greater. The current may correspond to C2 or C3 asshown in FIGS. 15A and 15B. In some embodiments, the upper or lowertorque limit may have a corresponding current value of 100 mA(milliamps), 200 mA, 300 mA, 400 mA, 500 mA, 600 mA, 700 mA, 800 mA, 900mA, 1,000 mA, 1,100 mA, 1,200 mA, 1,300 mA, 1,400 mA, 1,500 mA, 1,600mA, 1,700 mA, 1,800 mA, 1,900 mA, 2,000 mA, 2,100 mA, 2,200 mA, 2,300mA, 2,400 mA, 2,500 mA, 2,600 mA, 2,700 mA, 2,800 mA, 2,900 mA, or 3,000mA, or within +/−10% of any of these values. Various voltages may beused for the various limits. The voltages may be 5V, 5.5V, 6V, 6.5V, 7V,7.5V, 8V, 8.5V or 9V, or within +/−10% of any of these values. Thevoltages may be 8.4V or 7.4 V.

FIG. 16B is a flow chart showing an embodiment of a method 920 fordetermining torque limits for control of the prosthetic wrist 100. Themethod 920 begins with step 922 wherein the prosthetic wrist 100 isrotated. This may be a rotation command sent from the controller 820 tothe actuator 810. The method 920 then moves to step 924 wherein thestage or stages of rotation are determined. Step 924 may include theanalysis described herein with respect to FIGS. 15A-15C. Step 924 mayinclude determining stage one, two, three, four, and/or five for theprosthetic wrist 100. Step 924 may include determining whether therotation is loaded, unloaded or under a progressive loading condition.

The method 920 then moves to step 926 wherein the current at each stageis determined. Step 926 may include the various analyses describedherein with respect to FIGS. 15A-15C. For example, in step 926 local orglobal maximums or peaks may be identified in the current versus timerelationship to identify an upper current limit. Step 926 may includedetermining the running current in order to determine the lower currentlimit. Step 926 may include determining values for C2 and/or C3.

The method 920 then moves to step 928 wherein the torque limits aredetermined based on the currents. Step 928 may include the variousanalyses described herein with respect to FIGS. 15A-15C. For example, instep 928 the corresponding torques for the current values C2 and/or C3may be identified. The torque limits may be associated with variousstages of rotation as described herein. These torque limits may then beimplemented into the controller for the prosthetic wrist 200, forexample in the method 900 described herein.

A person/one having ordinary skill in the art would appreciate that anyof the various illustrative logical blocks, modules, controllers, means,circuits, and algorithm steps or blocks described in connection with theaspects disclosed herein can be implemented as electronic hardware(e.g., a digital implementation, an analog implementation, or acombination of the two, which can be designed using source coding orsome other technique), various forms of program or design codeincorporating instructions (which can be referred to herein, forconvenience, as “software” or a “software module”), or combinations ofboth. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps or blocks have been described above generally in terms oftheir functionality. Whether such functionality is implemented ashardware or software depends upon the particular application and designconstraints imposed on the overall system. Skilled artisans canimplement the described functionality in varying ways for eachparticular application, but such implementation decisions should not beinterpreted as causing a departure from the scope of the presentdisclosure.

A person having ordinary skill in the art would further understand thatinformation and signals can be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that can bereferenced throughout the above description can be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein and in connection withthe figures can be implemented within or performed by an integratedcircuit (IC), an access terminal, or an access point. The IC can includea general purpose processor, a digital signal processor (DSP), anapplication specific integrated circuit (ASIC), a field programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, electrical components,optical components, mechanical components, or any combination thereofdesigned to perform the functions described herein, and can executecodes or instructions that reside within the IC, outside of the IC, orboth. The logical blocks, modules, and circuits can include antennasand/or transceivers to communicate with various components within thenetwork or within the device.

A general purpose processor can be a microprocessor, but in thealternative, the processor can be any conventional processor,controller, microcontroller, or state machine. A processor can also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration. The functionality of the modules can be implemented insome other manner as taught herein. The functionality described herein(e.g., with regard to one or more of the accompanying figures) cancorrespond in some aspects any similarly designated “means for”functionality in the appended claims.

If implemented in software, the functions can be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. The steps or blocks of a methods or algorithmsdisclosed herein can be implemented in a processor-executable softwaremodule which can reside on a computer-readable medium. Computer-readablemedia includes both computer storage media and communication mediaincluding any medium that can be enabled to transfer a computer programfrom one place to another. A storage media can be any available mediathat can be accessed by a computer. By way of example, and notlimitation, such computer-readable media can include RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to storedesired program code in the form of instructions or data structures andthat can be accessed by a computer. Also, any connection can be properlytermed a computer-readable medium. Disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk, and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media. Additionally, the operations of a method oralgorithm can reside as one or any combination or set of codes andinstructions on a machine readable medium and computer-readable medium,which can be incorporated into a computer program product.

It is understood that any specific order or hierarchy of steps or blocksin any disclosed process is an example of a sample approach. Based upondesign preferences, it is understood that the specific order orhierarchy of steps or blocks in the processes can be rearranged whileremaining within the scope of the present disclosure. Any accompanyingmethod claims present elements of the various steps or blocks in asample order, and are not meant to be limited to the specific order orhierarchy presented.

Various modifications to the implementations described in thisdisclosure can be readily apparent to those skilled in the art, and thegeneric principles defined herein can be applied to otherimplementations without departing from the spirit or scope of thisdisclosure. Thus, the disclosure is not intended to be limited to theimplementations shown herein, but is to be accorded the widest scopeconsistent with the claims, the principles and the novel featuresdisclosed herein. The word “example” is used exclusively herein to mean“serving as an example, instance, or illustration.” Any implementationdescribed herein as “example” is not necessarily to be construed aspreferred or advantageous over other implementations.

Certain features that are described in this specification in the contextof separate implementations also can be implemented in combination in asingle implementation. Conversely, various features that are describedin the context of a single implementation also can be implemented inmultiple implementations separately or in any suitable sub-combination.Moreover, although features can be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination can be directed to asub-combination or variation of a sub-combination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. In certain circumstances, multitasking and parallel processingcan be advantageous. Moreover, the separation of various systemcomponents in the implementations described above should not beunderstood as requiring such separation in all implementations, and itshould be understood that the described program components and systemscan generally be integrated together in a single software product orpackaged into multiple software products. Additionally, otherimplementations are within the scope of the following claims. In somecases, the actions recited in the claims can be performed in a differentorder and still achieve desirable results.

It will be understood by those within the art that, in general, termsused herein are generally intended as “open” terms (e.g., the term“including” should be interpreted as “including but not limited to,” theterm “having” should be interpreted as “having at least,” the term“includes” should be interpreted as “includes but is not limited to,”etc.). It will be further understood by those within the art that if aspecific number of an introduced claim recitation is intended, such anintent will be explicitly recited in the claim, and in the absence ofsuch recitation no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage of theintroductory phrases “at least one” and “one or more” to introduce claimrecitations. However, the use of such phrases should not be construed toimply that the introduction of a claim recitation by the indefinitearticles “a” or “an” limits any particular claim containing suchintroduced claim recitation to embodiments containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a” and/or “an” should typically be interpreted to mean “atleast one” or “one or more”); the same holds true for the use ofdefinite articles used to introduce claim recitations. In addition, evenif a specific number of an introduced claim recitation is explicitlyrecited, those skilled in the art will recognize that such recitationshould typically be interpreted to mean at least the recited number(e.g., the bare recitation of “two recitations,” without othermodifiers, typically means at least two recitations, or two or morerecitations). Furthermore, in those instances where a conventionanalogous to “at least one of A, B, and C, etc.” is used, in generalsuch a construction is intended in the sense one having skill in the artwould understand the convention (e.g., “a system having at least one ofA, B, and C” would include but not be limited to systems that have Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). In those instances where aconvention analogous to “at least one of A, B, or C, etc.” is used, ingeneral such a construction is intended in the sense one having skill inthe art would understand the convention (e.g., “a system having at leastone of A, B, or C” would include but not be limited to systems that haveA alone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). It will be furtherunderstood by those within the art that virtually any disjunctive wordand/or phrase presenting two or more alternative terms, whether in thedescription, claims, or drawings, should be understood to contemplatethe possibilities of including one of the terms, either of the terms, orboth terms. For example, the phrase “A or B” will be understood toinclude the possibilities of “A” or “B” or “A and B.”

What is claimed is:
 1. A prosthetic wrist comprising: a body; anactuator; and a coupling.